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	<link rel="modulepreload" href="/docs/tokenizers/pr_2012/en/_app/immutable/chunks/TokenizersLanguageContent.0fc17a7a.js"><!-- HEAD_svelte-u9bgzb_START --><meta name="hf:doc:metadata" content="{"title":"The tokenization pipeline","local":"the-tokenization-pipeline","sections":[{"title":"Normalization","local":"normalization","sections":[],"depth":2},{"title":"Pre-Tokenization","local":"pre-tokenization","sections":[],"depth":2},{"title":"Model","local":"model","sections":[],"depth":2},{"title":"Post-Processing","local":"post-processing","sections":[],"depth":2},{"title":"All together: a BERT tokenizer from scratch","local":"all-together-a-bert-tokenizer-from-scratch","sections":[],"depth":2},{"title":"Decoding","local":"decoding","sections":[],"depth":2}],"depth":1}"><!-- HEAD_svelte-u9bgzb_END --> <p></p> <div class="items-center shrink-0 min-w-[100px] max-sm:min-w-[50px] justify-end ml-auto flex" style="float: right; margin-left: 10px; display: inline-flex; position: relative; z-index: 10;"><div class="inline-flex rounded-md max-sm:rounded-sm"><button class="inline-flex items-center gap-1 h-7 max-sm:h-7 px-2 max-sm:px-1.5 text-sm font-medium text-gray-800 border border-r-0 rounded-l-md max-sm:rounded-l-sm border-gray-200 bg-white hover:shadow-inner dark:border-gray-850 dark:bg-gray-950 dark:text-gray-200 dark:hover:bg-gray-800" aria-live="polite"><span class="inline-flex items-center justify-center rounded-md p-0.5 max-sm:p-0 hover:text-gray-800 dark:hover:text-gray-200"><svg class="sm:size-3.5 size-3" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg></span> <span>Copy page</span></button> <button class="inline-flex items-center justify-center w-6 max-sm:w-5 h-7 max-sm:h-7 disabled:pointer-events-none text-sm text-gray-500 hover:text-gray-700 dark:hover:text-white rounded-r-md max-sm:rounded-r-sm border border-l transition border-gray-200 bg-white hover:shadow-inner dark:border-gray-850 dark:bg-gray-950 dark:text-gray-200 dark:hover:bg-gray-800" aria-haspopup="menu" aria-expanded="false" aria-label="Open copy menu"><svg class="transition-transform text-gray-400 overflow-visible sm:size-3.5 size-3 rotate-0" width="1em" height="1em" viewBox="0 0 12 7" fill="none" xmlns="http://www.w3.org/2000/svg"><path d="M1 1L6 6L11 1" stroke="currentColor"></path></svg></button></div> </div> <h1 class="relative group"><a id="the-tokenization-pipeline" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#the-tokenization-pipeline"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>The tokenization pipeline</span></h1> <p data-svelte-h="svelte-jozml5">When calling <code>Tokenizer.encode</code> or
	<code>Tokenizer.encode_batch</code>, the input
	text(s) go through the following pipeline:</p> <ul data-svelte-h="svelte-1rz3n8j"><li><code>normalization</code></li> <li><code>pre-tokenization</code></li> <li><code>model</code></li> <li><code>post-processing</code></li></ul> <p data-svelte-h="svelte-1rtvet7">We’ll see in details what happens during each of those steps in detail,
	as well as when you want to <code>decode <decoding></code> some token ids, and how the 🤗 Tokenizers library allows you
	to customize each of those steps to your needs. If you’re already
	familiar with those steps and want to learn by seeing some code, jump to
	<code>our BERT from scratch example <example></code>.</p> <p data-svelte-h="svelte-8zxp30">For the examples that require a <code>Tokenizer</code> we will use the tokenizer we trained in the
	<code>quicktour</code>, which you can load with:</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M15.84.5a16.4,16.4,0,0,0-3.57.32C9.1,1.39,8.53,2.53,8.53,4.64V7.48H16v1H5.77a4.73,4.73,0,0,0-4.7,3.74,14.82,14.82,0,0,0,0,7.54c.57,2.28,1.86,3.82,4,3.82h2.6V20.14a4.73,4.73,0,0,1,4.63-4.63h7.38a3.72,3.72,0,0,0,3.73-3.73V4.64A4.16,4.16,0,0,0,19.65.82,20.49,20.49,0,0,0,15.84.5ZM11.78,2.77a1.39,1.39,0,0,1,1.38,1.46,1.37,1.37,0,0,1-1.38,1.38A1.42,1.42,0,0,1,10.4,4.23,1.44,1.44,0,0,1,11.78,2.77Z" fill="#5a9fd4"></path><path d="M16.16,31.5a16.4,16.4,0,0,0,3.57-.32c3.17-.57,3.74-1.71,3.74-3.82V24.52H16v-1H26.23a4.73,4.73,0,0,0,4.7-3.74,14.82,14.82,0,0,0,0-7.54c-.57-2.28-1.86-3.82-4-3.82h-2.6v3.41a4.73,4.73,0,0,1-4.63,4.63H12.35a3.72,3.72,0,0,0-3.73,3.73v7.14a4.16,4.16,0,0,0,3.73,3.82A20.49,20.49,0,0,0,16.16,31.5Zm4.06-2.27a1.39,1.39,0,0,1-1.38-1.46,1.37,1.37,0,0,1,1.38-1.38,1.42,1.42,0,0,1,1.38,1.38A1.44,1.44,0,0,1,20.22,29.23Z" fill="#ffd43b"></path></svg> Python </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" preserveAspectRatio="xMidYMid meet" width="1em" height="1em" viewBox="0 0 32 32"><path 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class="language-select"> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START --><span class="hljs-keyword">from</span> tokenizers <span class="hljs-keyword">import</span> Tokenizer
	tokenizer = Tokenizer.from_file(<span class="hljs-string">"data/tokenizer-wiki.json"</span>)<!-- HTML_TAG_END --></pre></div> </div> <h2 class="relative group"><a id="normalization" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#normalization"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Normalization</span></h2> <p data-svelte-h="svelte-qddrd9">Normalization is, in a nutshell, a set of operations you apply to a raw
	string to make it less random or “cleaner”. Common operations include
	stripping whitespace, removing accented characters or lowercasing all
	text. If you’re familiar with <a href="https://unicode.org/reports/tr15" rel="nofollow">Unicode
	normalization</a>, it is also a very
	common normalization operation applied in most tokenizers.</p> <p data-svelte-h="svelte-u21ffr">Each normalization operation is represented in the 🤗 Tokenizers library
	by a <code>Normalizer</code>, and you can combine
	several of those by using a <code>normalizers.Sequence</code>. Here is a normalizer applying NFD Unicode normalization
	and removing accents as an example:</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M15.84.5a16.4,16.4,0,0,0-3.57.32C9.1,1.39,8.53,2.53,8.53,4.64V7.48H16v1H5.77a4.73,4.73,0,0,0-4.7,3.74,14.82,14.82,0,0,0,0,7.54c.57,2.28,1.86,3.82,4,3.82h2.6V20.14a4.73,4.73,0,0,1,4.63-4.63h7.38a3.72,3.72,0,0,0,3.73-3.73V4.64A4.16,4.16,0,0,0,19.65.82,20.49,20.49,0,0,0,15.84.5ZM11.78,2.77a1.39,1.39,0,0,1,1.38,1.46,1.37,1.37,0,0,1-1.38,1.38A1.42,1.42,0,0,1,10.4,4.23,1.44,1.44,0,0,1,11.78,2.77Z" fill="#5a9fd4"></path><path d="M16.16,31.5a16.4,16.4,0,0,0,3.57-.32c3.17-.57,3.74-1.71,3.74-3.82V24.52H16v-1H26.23a4.73,4.73,0,0,0,4.7-3.74,14.82,14.82,0,0,0,0-7.54c-.57-2.28-1.86-3.82-4-3.82h-2.6v3.41a4.73,4.73,0,0,1-4.63,4.63H12.35a3.72,3.72,0,0,0-3.73,3.73v7.14a4.16,4.16,0,0,0,3.73,3.82A20.49,20.49,0,0,0,16.16,31.5Zm4.06-2.27a1.39,1.39,0,0,1-1.38-1.46,1.37,1.37,0,0,1,1.38-1.38,1.42,1.42,0,0,1,1.38,1.38A1.44,1.44,0,0,1,20.22,29.23Z" fill="#ffd43b"></path></svg> Python </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" preserveAspectRatio="xMidYMid meet" width="1em" height="1em" viewBox="0 0 32 32"><path d="M31.77,15.61l-1.34-.83c0-.13,0-.26,0-.39l1.16-1.08a.46.46,0,0,0,.14-.43.44.44,0,0,0-.29-.34L29.92,12l-.12-.38.92-1.28a.46.46,0,0,0,.06-.45.47.47,0,0,0-.36-.28l-1.55-.25L28.68,9l.66-1.44a.48.48,0,0,0,0-.45.46.46,0,0,0-.4-.2L27.32,7l-.25-.3.36-1.54a.46.46,0,0,0-.12-.43.46.46,0,0,0-.43-.13l-1.54.37L25,4.68l.06-1.58a.44.44,0,0,0-.21-.4.45.45,0,0,0-.45,0L23,3.32l-.35-.19L22.4,1.57a.46.46,0,0,0-.28-.35.48.48,0,0,0-.45.05l-1.28.92L20,2.08,19.46.6a.44.44,0,0,0-.34-.29.46.46,0,0,0-.43.14L17.62,1.6l-.39,0L16.39.22a.46.46,0,0,0-.78,0l-.83,1.34-.39,0L13.31.45a.46.46,0,0,0-.43-.14.44.44,0,0,0-.34.29L12,2.08l-.38.11-1.28-.92a.48.48,0,0,0-.45-.05.5.5,0,0,0-.28.35L9.35,3.13,9,3.32,7.57,2.66a.45.45,0,0,0-.45,0,.49.49,0,0,0-.21.4L7,4.68l-.31.25L5.13,4.56a.48.48,0,0,0-.44.13.46.46,0,0,0-.12.43l.36,1.54L4.68,7l-1.58,0a.46.46,0,0,0-.4.2.48.48,0,0,0,0,.45L3.32,9l-.19.35L1.57,9.6a.47.47,0,0,0-.35.28.48.48,0,0,0,.05.45l.92,1.28c0,.12-.07.25-.11.38L.6,12.54a.44.44,0,0,0-.29.34.46.46,0,0,0,.14.43L1.6,14.39l0,.39-1.35.83a.47.47,0,0,0,0,.78l1.35.84,0,.39L.45,18.69a.46.46,0,0,0-.14.43.44.44,0,0,0,.29.34L2.08,20c0,.13.07.26.11.39l-.92,1.28a.46.46,0,0,0-.05.44.45.45,0,0,0,.36.28l1.55.25.19.35-.65,1.44a.45.45,0,0,0,.43.65L4.68,25l.25.3-.36,1.54a.46.46,0,0,0,.12.43.48.48,0,0,0,.44.12l1.54-.36.3.25L6.91,28.9a.49.49,0,0,0,.21.4.48.48,0,0,0,.45,0L9,28.68l.35.19.26,1.56a.46.46,0,0,0,.27.35.48.48,0,0,0,.45-.05l1.28-.92.38.12.55,1.47a.47.47,0,0,0,.34.29.46.46,0,0,0,.43-.13l1.08-1.16.39,0,.83,1.34A.46.46,0,0,0,16,32a.47.47,0,0,0,.4-.22l.83-1.34.39,0,1.08,1.16a.46.46,0,0,0,.43.13.47.47,0,0,0,.34-.29L20,29.93l.38-.12,1.28.92a.48.48,0,0,0,.45.05.45.45,0,0,0,.27-.35l.26-1.56.35-.19,1.43.66a.48.48,0,0,0,.45,0,.49.49,0,0,0,.21-.4L25,27.32l.3-.25,1.54.36a.48.48,0,0,0,.44-.12.46.46,0,0,0,.12-.43l-.36-1.54.25-.3,1.58.05a.45.45,0,0,0,.43-.65L28.69,23l.19-.35,1.55-.25a.45.45,0,0,0,.36-.28.43.43,0,0,0-.06-.44l-.92-1.28.12-.39,1.48-.55a.44.44,0,0,0,.29-.34.46.46,0,0,0-.14-.43L30.4,17.62c0-.13,0-.26,0-.39l1.34-.84a.46.46,0,0,0,0-.78Zm-9,11.16A1,1,0,1,1,23.92,26a.95.95,0,0,1-1.14.73Zm-.45-3.09a.87.87,0,0,0-1,.67l-.48,2.22a11.74,11.74,0,0,1-9.75,0l-.48-2.23a.85.85,0,0,0-1-.66l-2,.42a14.67,14.67,0,0,1-1-1.2h9.58c.1,0,.18,0,.18-.12V19.35c0-.1-.08-.12-.18-.12h-2.8V17.08h3a1.9,1.9,0,0,1,1.86,1.62c.12.47.39,2,.57,2.5s.91,1.65,1.69,1.65h4.77l.17,0a11,11,0,0,1-1.08,1.27l-2-.43Zm-13.24,3A.94.94,0,0,1,8,26a1,1,0,1,1,1.13.73ZM5.45,12a1,1,0,0,1-1.74.77,1,1,0,0,1,.49-1.26A1,1,0,0,1,5.45,12ZM4.33,14.66l2.05-.91a.87.87,0,0,0,.44-1.15l-.42-.95H8.06v7.46H4.73a11.37,11.37,0,0,1-.45-3.21,10.41,10.41,0,0,1,.07-1.26Zm9-.73v-2.2h3.95c.2,0,1.44.24,1.44,1.16,0,.77-.95,1-1.73,1H13.32Zm14.34,2q0,.45,0,.87h-1.2c-.12,0-.17.08-.17.2v.55c0,1.3-.73,1.58-1.37,1.65s-1.29-.25-1.37-.63a4.13,4.13,0,0,0-1.91-3.21C22.79,14.59,24,13.49,24,12a3.76,3.76,0,0,0-1.83-3.09,5.22,5.22,0,0,0-2.52-.83H7.25a11.79,11.79,0,0,1,6.54-3.7l1.47,1.54a.87.87,0,0,0,1.22,0l1.64-1.57a11.69,11.69,0,0,1,8,5.72L25,12.64a.87.87,0,0,0,.44,1.14l2.16,1a11.46,11.46,0,0,1,.06,1.17ZM15.25,3.1a1,1,0,0,1,1.34,0,1,1,0,0,1,0,1.35,1,1,0,0,1-1.34,0,1,1,0,0,1,0-1.35Zm11.13,9a.94.94,0,0,1,1.25-.48,1,1,0,1,1-1.25.48Z" fill="currentColor"></path></svg> Rust </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 289"><path fill="#539E43" d="M128 288.464c-3.975 0-7.685-1.06-11.13-2.915l-35.247-20.936c-5.3-2.915-2.65-3.975-1.06-4.505c7.155-2.385 8.48-2.915 15.9-7.156c.796-.53 1.856-.265 2.65.265l27.032 16.166c1.06.53 2.385.53 3.18 0l105.74-61.217c1.06-.53 1.59-1.59 1.59-2.915V83.08c0-1.325-.53-2.385-1.59-2.915l-105.74-60.953c-1.06-.53-2.385-.53-3.18 0L20.405 80.166c-1.06.53-1.59 1.855-1.59 2.915v122.17c0 1.06.53 2.385 1.59 2.915l28.887 16.695c15.636 7.95 25.44-1.325 25.44-10.6V93.68c0-1.59 1.326-3.18 3.181-3.18h13.516c1.59 0 3.18 1.325 3.18 3.18v120.58c0 20.936-11.396 33.126-31.272 33.126c-6.095 0-10.865 0-24.38-6.625l-27.827-15.9C4.24 220.885 0 213.465 0 205.515V83.346C0 75.396 4.24 67.976 11.13 64L116.87 2.783c6.625-3.71 15.635-3.71 22.26 0L244.87 64C251.76 67.975 256 75.395 256 83.346v122.17c0 7.95-4.24 15.37-11.13 19.345L139.13 286.08c-3.445 1.59-7.42 2.385-11.13 2.385Zm32.596-84.009c-46.377 0-55.917-21.2-55.917-39.221c0-1.59 1.325-3.18 3.18-3.18h13.78c1.59 0 2.916 1.06 2.916 2.65c2.12 14.045 8.215 20.936 36.306 20.936c22.261 0 31.802-5.035 31.802-16.96c0-6.891-2.65-11.926-37.367-15.372c-28.886-2.915-46.907-9.275-46.907-32.33c0-21.467 18.02-34.187 48.232-34.187c33.921 0 50.617 11.66 52.737 37.101c0 .795-.265 1.59-.795 2.385c-.53.53-1.325 1.06-2.12 1.06h-13.78c-1.326 0-2.65-1.06-2.916-2.385c-3.18-14.575-11.395-19.345-33.126-19.345c-24.38 0-27.296 8.48-27.296 14.84c0 7.686 3.445 10.07 36.306 14.31c32.597 4.24 47.967 10.336 47.967 33.127c-.265 23.321-19.345 36.571-53.002 36.571Z"></path></svg> Node </div></div> <div class="language-select"> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START --><span class="hljs-keyword">from</span> tokenizers <span class="hljs-keyword">import</span> normalizers
	<span class="hljs-keyword">from</span> tokenizers.normalizers <span class="hljs-keyword">import</span> NFD, StripAccents
	normalizer = normalizers.<span class="hljs-type">Sequence</span>([NFD(), StripAccents()])<!-- HTML_TAG_END --></pre></div> </div> <p data-svelte-h="svelte-11fxjh0">You can manually test that normalizer by applying it to any string:</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M15.84.5a16.4,16.4,0,0,0-3.57.32C9.1,1.39,8.53,2.53,8.53,4.64V7.48H16v1H5.77a4.73,4.73,0,0,0-4.7,3.74,14.82,14.82,0,0,0,0,7.54c.57,2.28,1.86,3.82,4,3.82h2.6V20.14a4.73,4.73,0,0,1,4.63-4.63h7.38a3.72,3.72,0,0,0,3.73-3.73V4.64A4.16,4.16,0,0,0,19.65.82,20.49,20.49,0,0,0,15.84.5ZM11.78,2.77a1.39,1.39,0,0,1,1.38,1.46,1.37,1.37,0,0,1-1.38,1.38A1.42,1.42,0,0,1,10.4,4.23,1.44,1.44,0,0,1,11.78,2.77Z" fill="#5a9fd4"></path><path d="M16.16,31.5a16.4,16.4,0,0,0,3.57-.32c3.17-.57,3.74-1.71,3.74-3.82V24.52H16v-1H26.23a4.73,4.73,0,0,0,4.7-3.74,14.82,14.82,0,0,0,0-7.54c-.57-2.28-1.86-3.82-4-3.82h-2.6v3.41a4.73,4.73,0,0,1-4.63,4.63H12.35a3.72,3.72,0,0,0-3.73,3.73v7.14a4.16,4.16,0,0,0,3.73,3.82A20.49,20.49,0,0,0,16.16,31.5Zm4.06-2.27a1.39,1.39,0,0,1-1.38-1.46,1.37,1.37,0,0,1,1.38-1.38,1.42,1.42,0,0,1,1.38,1.38A1.44,1.44,0,0,1,20.22,29.23Z" fill="#ffd43b"></path></svg> Python </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" preserveAspectRatio="xMidYMid meet" width="1em" height="1em" viewBox="0 0 32 32"><path 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fill="currentColor"></path></svg> Rust </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 289"><path fill="#539E43" d="M128 288.464c-3.975 0-7.685-1.06-11.13-2.915l-35.247-20.936c-5.3-2.915-2.65-3.975-1.06-4.505c7.155-2.385 8.48-2.915 15.9-7.156c.796-.53 1.856-.265 2.65.265l27.032 16.166c1.06.53 2.385.53 3.18 0l105.74-61.217c1.06-.53 1.59-1.59 1.59-2.915V83.08c0-1.325-.53-2.385-1.59-2.915l-105.74-60.953c-1.06-.53-2.385-.53-3.18 0L20.405 80.166c-1.06.53-1.59 1.855-1.59 2.915v122.17c0 1.06.53 2.385 1.59 2.915l28.887 16.695c15.636 7.95 25.44-1.325 25.44-10.6V93.68c0-1.59 1.326-3.18 3.181-3.18h13.516c1.59 0 3.18 1.325 3.18 3.18v120.58c0 20.936-11.396 33.126-31.272 33.126c-6.095 0-10.865 0-24.38-6.625l-27.827-15.9C4.24 220.885 0 213.465 0 205.515V83.346C0 75.396 4.24 67.976 11.13 64L116.87 2.783c6.625-3.71 15.635-3.71 22.26 0L244.87 64C251.76 67.975 256 75.395 256 83.346v122.17c0 7.95-4.24 15.37-11.13 19.345L139.13 286.08c-3.445 1.59-7.42 2.385-11.13 2.385Zm32.596-84.009c-46.377 0-55.917-21.2-55.917-39.221c0-1.59 1.325-3.18 3.18-3.18h13.78c1.59 0 2.916 1.06 2.916 2.65c2.12 14.045 8.215 20.936 36.306 20.936c22.261 0 31.802-5.035 31.802-16.96c0-6.891-2.65-11.926-37.367-15.372c-28.886-2.915-46.907-9.275-46.907-32.33c0-21.467 18.02-34.187 48.232-34.187c33.921 0 50.617 11.66 52.737 37.101c0 .795-.265 1.59-.795 2.385c-.53.53-1.325 1.06-2.12 1.06h-13.78c-1.326 0-2.65-1.06-2.916-2.385c-3.18-14.575-11.395-19.345-33.126-19.345c-24.38 0-27.296 8.48-27.296 14.84c0 7.686 3.445 10.07 36.306 14.31c32.597 4.24 47.967 10.336 47.967 33.127c-.265 23.321-19.345 36.571-53.002 36.571Z"></path></svg> Node </div></div> <div class="language-select"> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START -->normalizer.normalize_str(<span class="hljs-string">"Héllò hôw are ü?"</span>)
	<span class="hljs-comment"># "Hello how are u?"</span><!-- HTML_TAG_END --></pre></div> </div> <p data-svelte-h="svelte-ph5t46">When building a <code>Tokenizer</code>, you can
	customize its normalizer by just changing the corresponding attribute:</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M15.84.5a16.4,16.4,0,0,0-3.57.32C9.1,1.39,8.53,2.53,8.53,4.64V7.48H16v1H5.77a4.73,4.73,0,0,0-4.7,3.74,14.82,14.82,0,0,0,0,7.54c.57,2.28,1.86,3.82,4,3.82h2.6V20.14a4.73,4.73,0,0,1,4.63-4.63h7.38a3.72,3.72,0,0,0,3.73-3.73V4.64A4.16,4.16,0,0,0,19.65.82,20.49,20.49,0,0,0,15.84.5ZM11.78,2.77a1.39,1.39,0,0,1,1.38,1.46,1.37,1.37,0,0,1-1.38,1.38A1.42,1.42,0,0,1,10.4,4.23,1.44,1.44,0,0,1,11.78,2.77Z" fill="#5a9fd4"></path><path d="M16.16,31.5a16.4,16.4,0,0,0,3.57-.32c3.17-.57,3.74-1.71,3.74-3.82V24.52H16v-1H26.23a4.73,4.73,0,0,0,4.7-3.74,14.82,14.82,0,0,0,0-7.54c-.57-2.28-1.86-3.82-4-3.82h-2.6v3.41a4.73,4.73,0,0,1-4.63,4.63H12.35a3.72,3.72,0,0,0-3.73,3.73v7.14a4.16,4.16,0,0,0,3.73,3.82A20.49,20.49,0,0,0,16.16,31.5Zm4.06-2.27a1.39,1.39,0,0,1-1.38-1.46,1.37,1.37,0,0,1,1.38-1.38,1.42,1.42,0,0,1,1.38,1.38A1.44,1.44,0,0,1,20.22,29.23Z" fill="#ffd43b"></path></svg> Python </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" preserveAspectRatio="xMidYMid meet" width="1em" height="1em" viewBox="0 0 32 32"><path d="M31.77,15.61l-1.34-.83c0-.13,0-.26,0-.39l1.16-1.08a.46.46,0,0,0,.14-.43.44.44,0,0,0-.29-.34L29.92,12l-.12-.38.92-1.28a.46.46,0,0,0,.06-.45.47.47,0,0,0-.36-.28l-1.55-.25L28.68,9l.66-1.44a.48.48,0,0,0,0-.45.46.46,0,0,0-.4-.2L27.32,7l-.25-.3.36-1.54a.46.46,0,0,0-.12-.43.46.46,0,0,0-.43-.13l-1.54.37L25,4.68l.06-1.58a.44.44,0,0,0-.21-.4.45.45,0,0,0-.45,0L23,3.32l-.35-.19L22.4,1.57a.46.46,0,0,0-.28-.35.48.48,0,0,0-.45.05l-1.28.92L20,2.08,19.46.6a.44.44,0,0,0-.34-.29.46.46,0,0,0-.43.14L17.62,1.6l-.39,0L16.39.22a.46.46,0,0,0-.78,0l-.83,1.34-.39,0L13.31.45a.46.46,0,0,0-.43-.14.44.44,0,0,0-.34.29L12,2.08l-.38.11-1.28-.92a.48.48,0,0,0-.45-.05.5.5,0,0,0-.28.35L9.35,3.13,9,3.32,7.57,2.66a.45.45,0,0,0-.45,0,.49.49,0,0,0-.21.4L7,4.68l-.31.25L5.13,4.56a.48.48,0,0,0-.44.13.46.46,0,0,0-.12.43l.36,1.54L4.68,7l-1.58,0a.46.46,0,0,0-.4.2.48.48,0,0,0,0,.45L3.32,9l-.19.35L1.57,9.6a.47.47,0,0,0-.35.28.48.48,0,0,0,.05.45l.92,1.28c0,.12-.07.25-.11.38L.6,12.54a.44.44,0,0,0-.29.34.46.46,0,0,0,.14.43L1.6,14.39l0,.39-1.35.83a.47.47,0,0,0,0,.78l1.35.84,0,.39L.45,18.69a.46.46,0,0,0-.14.43.44.44,0,0,0,.29.34L2.08,20c0,.13.07.26.11.39l-.92,1.28a.46.46,0,0,0-.05.44.45.45,0,0,0,.36.28l1.55.25.19.35-.65,1.44a.45.45,0,0,0,.43.65L4.68,25l.25.3-.36,1.54a.46.46,0,0,0,.12.43.48.48,0,0,0,.44.12l1.54-.36.3.25L6.91,28.9a.49.49,0,0,0,.21.4.48.48,0,0,0,.45,0L9,28.68l.35.19.26,1.56a.46.46,0,0,0,.27.35.48.48,0,0,0,.45-.05l1.28-.92.38.12.55,1.47a.47.47,0,0,0,.34.29.46.46,0,0,0,.43-.13l1.08-1.16.39,0,.83,1.34A.46.46,0,0,0,16,32a.47.47,0,0,0,.4-.22l.83-1.34.39,0,1.08,1.16a.46.46,0,0,0,.43.13.47.47,0,0,0,.34-.29L20,29.93l.38-.12,1.28.92a.48.48,0,0,0,.45.05.45.45,0,0,0,.27-.35l.26-1.56.35-.19,1.43.66a.48.48,0,0,0,.45,0,.49.49,0,0,0,.21-.4L25,27.32l.3-.25,1.54.36a.48.48,0,0,0,.44-.12.46.46,0,0,0,.12-.43l-.36-1.54.25-.3,1.58.05a.45.45,0,0,0,.43-.65L28.69,23l.19-.35,1.55-.25a.45.45,0,0,0,.36-.28.43.43,0,0,0-.06-.44l-.92-1.28.12-.39,1.48-.55a.44.44,0,0,0,.29-.34.46.46,0,0,0-.14-.43L30.4,17.62c0-.13,0-.26,0-.39l1.34-.84a.46.46,0,0,0,0-.78Zm-9,11.16A1,1,0,1,1,23.92,26a.95.95,0,0,1-1.14.73Zm-.45-3.09a.87.87,0,0,0-1,.67l-.48,2.22a11.74,11.74,0,0,1-9.75,0l-.48-2.23a.85.85,0,0,0-1-.66l-2,.42a14.67,14.67,0,0,1-1-1.2h9.58c.1,0,.18,0,.18-.12V19.35c0-.1-.08-.12-.18-.12h-2.8V17.08h3a1.9,1.9,0,0,1,1.86,1.62c.12.47.39,2,.57,2.5s.91,1.65,1.69,1.65h4.77l.17,0a11,11,0,0,1-1.08,1.27l-2-.43Zm-13.24,3A.94.94,0,0,1,8,26a1,1,0,1,1,1.13.73ZM5.45,12a1,1,0,0,1-1.74.77,1,1,0,0,1,.49-1.26A1,1,0,0,1,5.45,12ZM4.33,14.66l2.05-.91a.87.87,0,0,0,.44-1.15l-.42-.95H8.06v7.46H4.73a11.37,11.37,0,0,1-.45-3.21,10.41,10.41,0,0,1,.07-1.26Zm9-.73v-2.2h3.95c.2,0,1.44.24,1.44,1.16,0,.77-.95,1-1.73,1H13.32Zm14.34,2q0,.45,0,.87h-1.2c-.12,0-.17.08-.17.2v.55c0,1.3-.73,1.58-1.37,1.65s-1.29-.25-1.37-.63a4.13,4.13,0,0,0-1.91-3.21C22.79,14.59,24,13.49,24,12a3.76,3.76,0,0,0-1.83-3.09,5.22,5.22,0,0,0-2.52-.83H7.25a11.79,11.79,0,0,1,6.54-3.7l1.47,1.54a.87.87,0,0,0,1.22,0l1.64-1.57a11.69,11.69,0,0,1,8,5.72L25,12.64a.87.87,0,0,0,.44,1.14l2.16,1a11.46,11.46,0,0,1,.06,1.17ZM15.25,3.1a1,1,0,0,1,1.34,0,1,1,0,0,1,0,1.35,1,1,0,0,1-1.34,0,1,1,0,0,1,0-1.35Zm11.13,9a.94.94,0,0,1,1.25-.48,1,1,0,1,1-1.25.48Z" fill="currentColor"></path></svg> Rust </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 289"><path fill="#539E43" d="M128 288.464c-3.975 0-7.685-1.06-11.13-2.915l-35.247-20.936c-5.3-2.915-2.65-3.975-1.06-4.505c7.155-2.385 8.48-2.915 15.9-7.156c.796-.53 1.856-.265 2.65.265l27.032 16.166c1.06.53 2.385.53 3.18 0l105.74-61.217c1.06-.53 1.59-1.59 1.59-2.915V83.08c0-1.325-.53-2.385-1.59-2.915l-105.74-60.953c-1.06-.53-2.385-.53-3.18 0L20.405 80.166c-1.06.53-1.59 1.855-1.59 2.915v122.17c0 1.06.53 2.385 1.59 2.915l28.887 16.695c15.636 7.95 25.44-1.325 25.44-10.6V93.68c0-1.59 1.326-3.18 3.181-3.18h13.516c1.59 0 3.18 1.325 3.18 3.18v120.58c0 20.936-11.396 33.126-31.272 33.126c-6.095 0-10.865 0-24.38-6.625l-27.827-15.9C4.24 220.885 0 213.465 0 205.515V83.346C0 75.396 4.24 67.976 11.13 64L116.87 2.783c6.625-3.71 15.635-3.71 22.26 0L244.87 64C251.76 67.975 256 75.395 256 83.346v122.17c0 7.95-4.24 15.37-11.13 19.345L139.13 286.08c-3.445 1.59-7.42 2.385-11.13 2.385Zm32.596-84.009c-46.377 0-55.917-21.2-55.917-39.221c0-1.59 1.325-3.18 3.18-3.18h13.78c1.59 0 2.916 1.06 2.916 2.65c2.12 14.045 8.215 20.936 36.306 20.936c22.261 0 31.802-5.035 31.802-16.96c0-6.891-2.65-11.926-37.367-15.372c-28.886-2.915-46.907-9.275-46.907-32.33c0-21.467 18.02-34.187 48.232-34.187c33.921 0 50.617 11.66 52.737 37.101c0 .795-.265 1.59-.795 2.385c-.53.53-1.325 1.06-2.12 1.06h-13.78c-1.326 0-2.65-1.06-2.916-2.385c-3.18-14.575-11.395-19.345-33.126-19.345c-24.38 0-27.296 8.48-27.296 14.84c0 7.686 3.445 10.07 36.306 14.31c32.597 4.24 47.967 10.336 47.967 33.127c-.265 23.321-19.345 36.571-53.002 36.571Z"></path></svg> Node </div></div> <div class="language-select"> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START -->tokenizer.normalizer = normalizer<!-- HTML_TAG_END --></pre></div> </div> <p data-svelte-h="svelte-c5if5y">Of course, if you change the way a tokenizer applies normalization, you
	should probably retrain it from scratch afterward.</p> <h2 class="relative group"><a id="pre-tokenization" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#pre-tokenization"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Pre-Tokenization</span></h2> <p data-svelte-h="svelte-17w2pja">Pre-tokenization is the act of splitting a text into smaller objects
	that give an upper bound to what your tokens will be at the end of
	training. A good way to think of this is that the pre-tokenizer will
	split your text into “words” and then, your final tokens will be parts
	of those words.</p> <p data-svelte-h="svelte-8vbxhw">An easy way to pre-tokenize inputs is to split on spaces and
	punctuations, which is done by the
	<code>pre_tokenizers.Whitespace</code>
	pre-tokenizer:</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M15.84.5a16.4,16.4,0,0,0-3.57.32C9.1,1.39,8.53,2.53,8.53,4.64V7.48H16v1H5.77a4.73,4.73,0,0,0-4.7,3.74,14.82,14.82,0,0,0,0,7.54c.57,2.28,1.86,3.82,4,3.82h2.6V20.14a4.73,4.73,0,0,1,4.63-4.63h7.38a3.72,3.72,0,0,0,3.73-3.73V4.64A4.16,4.16,0,0,0,19.65.82,20.49,20.49,0,0,0,15.84.5ZM11.78,2.77a1.39,1.39,0,0,1,1.38,1.46,1.37,1.37,0,0,1-1.38,1.38A1.42,1.42,0,0,1,10.4,4.23,1.44,1.44,0,0,1,11.78,2.77Z" fill="#5a9fd4"></path><path d="M16.16,31.5a16.4,16.4,0,0,0,3.57-.32c3.17-.57,3.74-1.71,3.74-3.82V24.52H16v-1H26.23a4.73,4.73,0,0,0,4.7-3.74,14.82,14.82,0,0,0,0-7.54c-.57-2.28-1.86-3.82-4-3.82h-2.6v3.41a4.73,4.73,0,0,1-4.63,4.63H12.35a3.72,3.72,0,0,0-3.73,3.73v7.14a4.16,4.16,0,0,0,3.73,3.82A20.49,20.49,0,0,0,16.16,31.5Zm4.06-2.27a1.39,1.39,0,0,1-1.38-1.46,1.37,1.37,0,0,1,1.38-1.38,1.42,1.42,0,0,1,1.38,1.38A1.44,1.44,0,0,1,20.22,29.23Z" fill="#ffd43b"></path></svg> Python </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" preserveAspectRatio="xMidYMid meet" width="1em" height="1em" viewBox="0 0 32 32"><path d="M31.77,15.61l-1.34-.83c0-.13,0-.26,0-.39l1.16-1.08a.46.46,0,0,0,.14-.43.44.44,0,0,0-.29-.34L29.92,12l-.12-.38.92-1.28a.46.46,0,0,0,.06-.45.47.47,0,0,0-.36-.28l-1.55-.25L28.68,9l.66-1.44a.48.48,0,0,0,0-.45.46.46,0,0,0-.4-.2L27.32,7l-.25-.3.36-1.54a.46.46,0,0,0-.12-.43.46.46,0,0,0-.43-.13l-1.54.37L25,4.68l.06-1.58a.44.44,0,0,0-.21-.4.45.45,0,0,0-.45,0L23,3.32l-.35-.19L22.4,1.57a.46.46,0,0,0-.28-.35.48.48,0,0,0-.45.05l-1.28.92L20,2.08,19.46.6a.44.44,0,0,0-.34-.29.46.46,0,0,0-.43.14L17.62,1.6l-.39,0L16.39.22a.46.46,0,0,0-.78,0l-.83,1.34-.39,0L13.31.45a.46.46,0,0,0-.43-.14.44.44,0,0,0-.34.29L12,2.08l-.38.11-1.28-.92a.48.48,0,0,0-.45-.05.5.5,0,0,0-.28.35L9.35,3.13,9,3.32,7.57,2.66a.45.45,0,0,0-.45,0,.49.49,0,0,0-.21.4L7,4.68l-.31.25L5.13,4.56a.48.48,0,0,0-.44.13.46.46,0,0,0-.12.43l.36,1.54L4.68,7l-1.58,0a.46.46,0,0,0-.4.2.48.48,0,0,0,0,.45L3.32,9l-.19.35L1.57,9.6a.47.47,0,0,0-.35.28.48.48,0,0,0,.05.45l.92,1.28c0,.12-.07.25-.11.38L.6,12.54a.44.44,0,0,0-.29.34.46.46,0,0,0,.14.43L1.6,14.39l0,.39-1.35.83a.47.47,0,0,0,0,.78l1.35.84,0,.39L.45,18.69a.46.46,0,0,0-.14.43.44.44,0,0,0,.29.34L2.08,20c0,.13.07.26.11.39l-.92,1.28a.46.46,0,0,0-.05.44.45.45,0,0,0,.36.28l1.55.25.19.35-.65,1.44a.45.45,0,0,0,.43.65L4.68,25l.25.3-.36,1.54a.46.46,0,0,0,.12.43.48.48,0,0,0,.44.12l1.54-.36.3.25L6.91,28.9a.49.49,0,0,0,.21.4.48.48,0,0,0,.45,0L9,28.68l.35.19.26,1.56a.46.46,0,0,0,.27.35.48.48,0,0,0,.45-.05l1.28-.92.38.12.55,1.47a.47.47,0,0,0,.34.29.46.46,0,0,0,.43-.13l1.08-1.16.39,0,.83,1.34A.46.46,0,0,0,16,32a.47.47,0,0,0,.4-.22l.83-1.34.39,0,1.08,1.16a.46.46,0,0,0,.43.13.47.47,0,0,0,.34-.29L20,29.93l.38-.12,1.28.92a.48.48,0,0,0,.45.05.45.45,0,0,0,.27-.35l.26-1.56.35-.19,1.43.66a.48.48,0,0,0,.45,0,.49.49,0,0,0,.21-.4L25,27.32l.3-.25,1.54.36a.48.48,0,0,0,.44-.12.46.46,0,0,0,.12-.43l-.36-1.54.25-.3,1.58.05a.45.45,0,0,0,.43-.65L28.69,23l.19-.35,1.55-.25a.45.45,0,0,0,.36-.28.43.43,0,0,0-.06-.44l-.92-1.28.12-.39,1.48-.55a.44.44,0,0,0,.29-.34.46.46,0,0,0-.14-.43L30.4,17.62c0-.13,0-.26,0-.39l1.34-.84a.46.46,0,0,0,0-.78Zm-9,11.16A1,1,0,1,1,23.92,26a.95.95,0,0,1-1.14.73Zm-.45-3.09a.87.87,0,0,0-1,.67l-.48,2.22a11.74,11.74,0,0,1-9.75,0l-.48-2.23a.85.85,0,0,0-1-.66l-2,.42a14.67,14.67,0,0,1-1-1.2h9.58c.1,0,.18,0,.18-.12V19.35c0-.1-.08-.12-.18-.12h-2.8V17.08h3a1.9,1.9,0,0,1,1.86,1.62c.12.47.39,2,.57,2.5s.91,1.65,1.69,1.65h4.77l.17,0a11,11,0,0,1-1.08,1.27l-2-.43Zm-13.24,3A.94.94,0,0,1,8,26a1,1,0,1,1,1.13.73ZM5.45,12a1,1,0,0,1-1.74.77,1,1,0,0,1,.49-1.26A1,1,0,0,1,5.45,12ZM4.33,14.66l2.05-.91a.87.87,0,0,0,.44-1.15l-.42-.95H8.06v7.46H4.73a11.37,11.37,0,0,1-.45-3.21,10.41,10.41,0,0,1,.07-1.26Zm9-.73v-2.2h3.95c.2,0,1.44.24,1.44,1.16,0,.77-.95,1-1.73,1H13.32Zm14.34,2q0,.45,0,.87h-1.2c-.12,0-.17.08-.17.2v.55c0,1.3-.73,1.58-1.37,1.65s-1.29-.25-1.37-.63a4.13,4.13,0,0,0-1.91-3.21C22.79,14.59,24,13.49,24,12a3.76,3.76,0,0,0-1.83-3.09,5.22,5.22,0,0,0-2.52-.83H7.25a11.79,11.79,0,0,1,6.54-3.7l1.47,1.54a.87.87,0,0,0,1.22,0l1.64-1.57a11.69,11.69,0,0,1,8,5.72L25,12.64a.87.87,0,0,0,.44,1.14l2.16,1a11.46,11.46,0,0,1,.06,1.17ZM15.25,3.1a1,1,0,0,1,1.34,0,1,1,0,0,1,0,1.35,1,1,0,0,1-1.34,0,1,1,0,0,1,0-1.35Zm11.13,9a.94.94,0,0,1,1.25-.48,1,1,0,1,1-1.25.48Z" fill="currentColor"></path></svg> Rust </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 289"><path fill="#539E43" d="M128 288.464c-3.975 0-7.685-1.06-11.13-2.915l-35.247-20.936c-5.3-2.915-2.65-3.975-1.06-4.505c7.155-2.385 8.48-2.915 15.9-7.156c.796-.53 1.856-.265 2.65.265l27.032 16.166c1.06.53 2.385.53 3.18 0l105.74-61.217c1.06-.53 1.59-1.59 1.59-2.915V83.08c0-1.325-.53-2.385-1.59-2.915l-105.74-60.953c-1.06-.53-2.385-.53-3.18 0L20.405 80.166c-1.06.53-1.59 1.855-1.59 2.915v122.17c0 1.06.53 2.385 1.59 2.915l28.887 16.695c15.636 7.95 25.44-1.325 25.44-10.6V93.68c0-1.59 1.326-3.18 3.181-3.18h13.516c1.59 0 3.18 1.325 3.18 3.18v120.58c0 20.936-11.396 33.126-31.272 33.126c-6.095 0-10.865 0-24.38-6.625l-27.827-15.9C4.24 220.885 0 213.465 0 205.515V83.346C0 75.396 4.24 67.976 11.13 64L116.87 2.783c6.625-3.71 15.635-3.71 22.26 0L244.87 64C251.76 67.975 256 75.395 256 83.346v122.17c0 7.95-4.24 15.37-11.13 19.345L139.13 286.08c-3.445 1.59-7.42 2.385-11.13 2.385Zm32.596-84.009c-46.377 0-55.917-21.2-55.917-39.221c0-1.59 1.325-3.18 3.18-3.18h13.78c1.59 0 2.916 1.06 2.916 2.65c2.12 14.045 8.215 20.936 36.306 20.936c22.261 0 31.802-5.035 31.802-16.96c0-6.891-2.65-11.926-37.367-15.372c-28.886-2.915-46.907-9.275-46.907-32.33c0-21.467 18.02-34.187 48.232-34.187c33.921 0 50.617 11.66 52.737 37.101c0 .795-.265 1.59-.795 2.385c-.53.53-1.325 1.06-2.12 1.06h-13.78c-1.326 0-2.65-1.06-2.916-2.385c-3.18-14.575-11.395-19.345-33.126-19.345c-24.38 0-27.296 8.48-27.296 14.84c0 7.686 3.445 10.07 36.306 14.31c32.597 4.24 47.967 10.336 47.967 33.127c-.265 23.321-19.345 36.571-53.002 36.571Z"></path></svg> Node </div></div> <div class="language-select"> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START --><span class="hljs-keyword">from</span> tokenizers.pre_tokenizers <span class="hljs-keyword">import</span> Whitespace
	pre_tokenizer = Whitespace()
	pre_tokenizer.pre_tokenize_str(<span class="hljs-string">"Hello! How are you? I'm fine, thank you."</span>)
	<span class="hljs-comment"># [("Hello", (0, 5)), ("!", (5, 6)), ("How", (7, 10)), ("are", (11, 14)), ("you", (15, 18)),</span>
	<span class="hljs-comment"># ("?", (18, 19)), ("I", (20, 21)), ("'", (21, 22)), ('m', (22, 23)), ("fine", (24, 28)),</span>
	<span class="hljs-comment"># (",", (28, 29)), ("thank", (30, 35)), ("you", (36, 39)), (".", (39, 40))]</span><!-- HTML_TAG_END --></pre></div> </div> <p data-svelte-h="svelte-rrvwxs">The output is a list of tuples, with each tuple containing one word and
	its span in the original sentence (which is used to determine the final
	<code>offsets</code> of our <code>Encoding</code>). Note that splitting on
	punctuation will split contractions like <code>"I'm"</code> in this example.</p> <p data-svelte-h="svelte-1sxj246">You can combine together any <code>PreTokenizer</code> together. For instance, here is a pre-tokenizer that will
	split on space, punctuation and digits, separating numbers in their
	individual digits:</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M15.84.5a16.4,16.4,0,0,0-3.57.32C9.1,1.39,8.53,2.53,8.53,4.64V7.48H16v1H5.77a4.73,4.73,0,0,0-4.7,3.74,14.82,14.82,0,0,0,0,7.54c.57,2.28,1.86,3.82,4,3.82h2.6V20.14a4.73,4.73,0,0,1,4.63-4.63h7.38a3.72,3.72,0,0,0,3.73-3.73V4.64A4.16,4.16,0,0,0,19.65.82,20.49,20.49,0,0,0,15.84.5ZM11.78,2.77a1.39,1.39,0,0,1,1.38,1.46,1.37,1.37,0,0,1-1.38,1.38A1.42,1.42,0,0,1,10.4,4.23,1.44,1.44,0,0,1,11.78,2.77Z" fill="#5a9fd4"></path><path d="M16.16,31.5a16.4,16.4,0,0,0,3.57-.32c3.17-.57,3.74-1.71,3.74-3.82V24.52H16v-1H26.23a4.73,4.73,0,0,0,4.7-3.74,14.82,14.82,0,0,0,0-7.54c-.57-2.28-1.86-3.82-4-3.82h-2.6v3.41a4.73,4.73,0,0,1-4.63,4.63H12.35a3.72,3.72,0,0,0-3.73,3.73v7.14a4.16,4.16,0,0,0,3.73,3.82A20.49,20.49,0,0,0,16.16,31.5Zm4.06-2.27a1.39,1.39,0,0,1-1.38-1.46,1.37,1.37,0,0,1,1.38-1.38,1.42,1.42,0,0,1,1.38,1.38A1.44,1.44,0,0,1,20.22,29.23Z" fill="#ffd43b"></path></svg> Python </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" preserveAspectRatio="xMidYMid meet" width="1em" height="1em" viewBox="0 0 32 32"><path d="M31.77,15.61l-1.34-.83c0-.13,0-.26,0-.39l1.16-1.08a.46.46,0,0,0,.14-.43.44.44,0,0,0-.29-.34L29.92,12l-.12-.38.92-1.28a.46.46,0,0,0,.06-.45.47.47,0,0,0-.36-.28l-1.55-.25L28.68,9l.66-1.44a.48.48,0,0,0,0-.45.46.46,0,0,0-.4-.2L27.32,7l-.25-.3.36-1.54a.46.46,0,0,0-.12-.43.46.46,0,0,0-.43-.13l-1.54.37L25,4.68l.06-1.58a.44.44,0,0,0-.21-.4.45.45,0,0,0-.45,0L23,3.32l-.35-.19L22.4,1.57a.46.46,0,0,0-.28-.35.48.48,0,0,0-.45.05l-1.28.92L20,2.08,19.46.6a.44.44,0,0,0-.34-.29.46.46,0,0,0-.43.14L17.62,1.6l-.39,0L16.39.22a.46.46,0,0,0-.78,0l-.83,1.34-.39,0L13.31.45a.46.46,0,0,0-.43-.14.44.44,0,0,0-.34.29L12,2.08l-.38.11-1.28-.92a.48.48,0,0,0-.45-.05.5.5,0,0,0-.28.35L9.35,3.13,9,3.32,7.57,2.66a.45.45,0,0,0-.45,0,.49.49,0,0,0-.21.4L7,4.68l-.31.25L5.13,4.56a.48.48,0,0,0-.44.13.46.46,0,0,0-.12.43l.36,1.54L4.68,7l-1.58,0a.46.46,0,0,0-.4.2.48.48,0,0,0,0,.45L3.32,9l-.19.35L1.57,9.6a.47.47,0,0,0-.35.28.48.48,0,0,0,.05.45l.92,1.28c0,.12-.07.25-.11.38L.6,12.54a.44.44,0,0,0-.29.34.46.46,0,0,0,.14.43L1.6,14.39l0,.39-1.35.83a.47.47,0,0,0,0,.78l1.35.84,0,.39L.45,18.69a.46.46,0,0,0-.14.43.44.44,0,0,0,.29.34L2.08,20c0,.13.07.26.11.39l-.92,1.28a.46.46,0,0,0-.05.44.45.45,0,0,0,.36.28l1.55.25.19.35-.65,1.44a.45.45,0,0,0,.43.65L4.68,25l.25.3-.36,1.54a.46.46,0,0,0,.12.43.48.48,0,0,0,.44.12l1.54-.36.3.25L6.91,28.9a.49.49,0,0,0,.21.4.48.48,0,0,0,.45,0L9,28.68l.35.19.26,1.56a.46.46,0,0,0,.27.35.48.48,0,0,0,.45-.05l1.28-.92.38.12.55,1.47a.47.47,0,0,0,.34.29.46.46,0,0,0,.43-.13l1.08-1.16.39,0,.83,1.34A.46.46,0,0,0,16,32a.47.47,0,0,0,.4-.22l.83-1.34.39,0,1.08,1.16a.46.46,0,0,0,.43.13.47.47,0,0,0,.34-.29L20,29.93l.38-.12,1.28.92a.48.48,0,0,0,.45.05.45.45,0,0,0,.27-.35l.26-1.56.35-.19,1.43.66a.48.48,0,0,0,.45,0,.49.49,0,0,0,.21-.4L25,27.32l.3-.25,1.54.36a.48.48,0,0,0,.44-.12.46.46,0,0,0,.12-.43l-.36-1.54.25-.3,1.58.05a.45.45,0,0,0,.43-.65L28.69,23l.19-.35,1.55-.25a.45.45,0,0,0,.36-.28.43.43,0,0,0-.06-.44l-.92-1.28.12-.39,1.48-.55a.44.44,0,0,0,.29-.34.46.46,0,0,0-.14-.43L30.4,17.62c0-.13,0-.26,0-.39l1.34-.84a.46.46,0,0,0,0-.78Zm-9,11.16A1,1,0,1,1,23.92,26a.95.95,0,0,1-1.14.73Zm-.45-3.09a.87.87,0,0,0-1,.67l-.48,2.22a11.74,11.74,0,0,1-9.75,0l-.48-2.23a.85.85,0,0,0-1-.66l-2,.42a14.67,14.67,0,0,1-1-1.2h9.58c.1,0,.18,0,.18-.12V19.35c0-.1-.08-.12-.18-.12h-2.8V17.08h3a1.9,1.9,0,0,1,1.86,1.62c.12.47.39,2,.57,2.5s.91,1.65,1.69,1.65h4.77l.17,0a11,11,0,0,1-1.08,1.27l-2-.43Zm-13.24,3A.94.94,0,0,1,8,26a1,1,0,1,1,1.13.73ZM5.45,12a1,1,0,0,1-1.74.77,1,1,0,0,1,.49-1.26A1,1,0,0,1,5.45,12ZM4.33,14.66l2.05-.91a.87.87,0,0,0,.44-1.15l-.42-.95H8.06v7.46H4.73a11.37,11.37,0,0,1-.45-3.21,10.41,10.41,0,0,1,.07-1.26Zm9-.73v-2.2h3.95c.2,0,1.44.24,1.44,1.16,0,.77-.95,1-1.73,1H13.32Zm14.34,2q0,.45,0,.87h-1.2c-.12,0-.17.08-.17.2v.55c0,1.3-.73,1.58-1.37,1.65s-1.29-.25-1.37-.63a4.13,4.13,0,0,0-1.91-3.21C22.79,14.59,24,13.49,24,12a3.76,3.76,0,0,0-1.83-3.09,5.22,5.22,0,0,0-2.52-.83H7.25a11.79,11.79,0,0,1,6.54-3.7l1.47,1.54a.87.87,0,0,0,1.22,0l1.64-1.57a11.69,11.69,0,0,1,8,5.72L25,12.64a.87.87,0,0,0,.44,1.14l2.16,1a11.46,11.46,0,0,1,.06,1.17ZM15.25,3.1a1,1,0,0,1,1.34,0,1,1,0,0,1,0,1.35,1,1,0,0,1-1.34,0,1,1,0,0,1,0-1.35Zm11.13,9a.94.94,0,0,1,1.25-.48,1,1,0,1,1-1.25.48Z" fill="currentColor"></path></svg> Rust </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 289"><path fill="#539E43" d="M128 288.464c-3.975 0-7.685-1.06-11.13-2.915l-35.247-20.936c-5.3-2.915-2.65-3.975-1.06-4.505c7.155-2.385 8.48-2.915 15.9-7.156c.796-.53 1.856-.265 2.65.265l27.032 16.166c1.06.53 2.385.53 3.18 0l105.74-61.217c1.06-.53 1.59-1.59 1.59-2.915V83.08c0-1.325-.53-2.385-1.59-2.915l-105.74-60.953c-1.06-.53-2.385-.53-3.18 0L20.405 80.166c-1.06.53-1.59 1.855-1.59 2.915v122.17c0 1.06.53 2.385 1.59 2.915l28.887 16.695c15.636 7.95 25.44-1.325 25.44-10.6V93.68c0-1.59 1.326-3.18 3.181-3.18h13.516c1.59 0 3.18 1.325 3.18 3.18v120.58c0 20.936-11.396 33.126-31.272 33.126c-6.095 0-10.865 0-24.38-6.625l-27.827-15.9C4.24 220.885 0 213.465 0 205.515V83.346C0 75.396 4.24 67.976 11.13 64L116.87 2.783c6.625-3.71 15.635-3.71 22.26 0L244.87 64C251.76 67.975 256 75.395 256 83.346v122.17c0 7.95-4.24 15.37-11.13 19.345L139.13 286.08c-3.445 1.59-7.42 2.385-11.13 2.385Zm32.596-84.009c-46.377 0-55.917-21.2-55.917-39.221c0-1.59 1.325-3.18 3.18-3.18h13.78c1.59 0 2.916 1.06 2.916 2.65c2.12 14.045 8.215 20.936 36.306 20.936c22.261 0 31.802-5.035 31.802-16.96c0-6.891-2.65-11.926-37.367-15.372c-28.886-2.915-46.907-9.275-46.907-32.33c0-21.467 18.02-34.187 48.232-34.187c33.921 0 50.617 11.66 52.737 37.101c0 .795-.265 1.59-.795 2.385c-.53.53-1.325 1.06-2.12 1.06h-13.78c-1.326 0-2.65-1.06-2.916-2.385c-3.18-14.575-11.395-19.345-33.126-19.345c-24.38 0-27.296 8.48-27.296 14.84c0 7.686 3.445 10.07 36.306 14.31c32.597 4.24 47.967 10.336 47.967 33.127c-.265 23.321-19.345 36.571-53.002 36.571Z"></path></svg> Node </div></div> <div class="language-select"> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START --><span class="hljs-keyword">from</span> tokenizers <span class="hljs-keyword">import</span> pre_tokenizers
	<span class="hljs-keyword">from</span> tokenizers.pre_tokenizers <span class="hljs-keyword">import</span> Digits
	pre_tokenizer = pre_tokenizers.<span class="hljs-type">Sequence</span>([Whitespace(), Digits(individual_digits=<span class="hljs-literal">True</span>)])
	pre_tokenizer.pre_tokenize_str(<span class="hljs-string">"Call 911!"</span>)
	<span class="hljs-comment"># [("Call", (0, 4)), ("9", (5, 6)), ("1", (6, 7)), ("1", (7, 8)), ("!", (8, 9))]</span><!-- HTML_TAG_END --></pre></div> </div> <p data-svelte-h="svelte-1xkybhv">As we saw in the <code>quicktour</code>, you can
	customize the pre-tokenizer of a <code>Tokenizer</code> by just changing the corresponding attribute:</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M15.84.5a16.4,16.4,0,0,0-3.57.32C9.1,1.39,8.53,2.53,8.53,4.64V7.48H16v1H5.77a4.73,4.73,0,0,0-4.7,3.74,14.82,14.82,0,0,0,0,7.54c.57,2.28,1.86,3.82,4,3.82h2.6V20.14a4.73,4.73,0,0,1,4.63-4.63h7.38a3.72,3.72,0,0,0,3.73-3.73V4.64A4.16,4.16,0,0,0,19.65.82,20.49,20.49,0,0,0,15.84.5ZM11.78,2.77a1.39,1.39,0,0,1,1.38,1.46,1.37,1.37,0,0,1-1.38,1.38A1.42,1.42,0,0,1,10.4,4.23,1.44,1.44,0,0,1,11.78,2.77Z" fill="#5a9fd4"></path><path d="M16.16,31.5a16.4,16.4,0,0,0,3.57-.32c3.17-.57,3.74-1.71,3.74-3.82V24.52H16v-1H26.23a4.73,4.73,0,0,0,4.7-3.74,14.82,14.82,0,0,0,0-7.54c-.57-2.28-1.86-3.82-4-3.82h-2.6v3.41a4.73,4.73,0,0,1-4.63,4.63H12.35a3.72,3.72,0,0,0-3.73,3.73v7.14a4.16,4.16,0,0,0,3.73,3.82A20.49,20.49,0,0,0,16.16,31.5Zm4.06-2.27a1.39,1.39,0,0,1-1.38-1.46,1.37,1.37,0,0,1,1.38-1.38,1.42,1.42,0,0,1,1.38,1.38A1.44,1.44,0,0,1,20.22,29.23Z" fill="#ffd43b"></path></svg> Python </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" preserveAspectRatio="xMidYMid meet" width="1em" height="1em" viewBox="0 0 32 32"><path d="M31.77,15.61l-1.34-.83c0-.13,0-.26,0-.39l1.16-1.08a.46.46,0,0,0,.14-.43.44.44,0,0,0-.29-.34L29.92,12l-.12-.38.92-1.28a.46.46,0,0,0,.06-.45.47.47,0,0,0-.36-.28l-1.55-.25L28.68,9l.66-1.44a.48.48,0,0,0,0-.45.46.46,0,0,0-.4-.2L27.32,7l-.25-.3.36-1.54a.46.46,0,0,0-.12-.43.46.46,0,0,0-.43-.13l-1.54.37L25,4.68l.06-1.58a.44.44,0,0,0-.21-.4.45.45,0,0,0-.45,0L23,3.32l-.35-.19L22.4,1.57a.46.46,0,0,0-.28-.35.48.48,0,0,0-.45.05l-1.28.92L20,2.08,19.46.6a.44.44,0,0,0-.34-.29.46.46,0,0,0-.43.14L17.62,1.6l-.39,0L16.39.22a.46.46,0,0,0-.78,0l-.83,1.34-.39,0L13.31.45a.46.46,0,0,0-.43-.14.44.44,0,0,0-.34.29L12,2.08l-.38.11-1.28-.92a.48.48,0,0,0-.45-.05.5.5,0,0,0-.28.35L9.35,3.13,9,3.32,7.57,2.66a.45.45,0,0,0-.45,0,.49.49,0,0,0-.21.4L7,4.68l-.31.25L5.13,4.56a.48.48,0,0,0-.44.13.46.46,0,0,0-.12.43l.36,1.54L4.68,7l-1.58,0a.46.46,0,0,0-.4.2.48.48,0,0,0,0,.45L3.32,9l-.19.35L1.57,9.6a.47.47,0,0,0-.35.28.48.48,0,0,0,.05.45l.92,1.28c0,.12-.07.25-.11.38L.6,12.54a.44.44,0,0,0-.29.34.46.46,0,0,0,.14.43L1.6,14.39l0,.39-1.35.83a.47.47,0,0,0,0,.78l1.35.84,0,.39L.45,18.69a.46.46,0,0,0-.14.43.44.44,0,0,0,.29.34L2.08,20c0,.13.07.26.11.39l-.92,1.28a.46.46,0,0,0-.05.44.45.45,0,0,0,.36.28l1.55.25.19.35-.65,1.44a.45.45,0,0,0,.43.65L4.68,25l.25.3-.36,1.54a.46.46,0,0,0,.12.43.48.48,0,0,0,.44.12l1.54-.36.3.25L6.91,28.9a.49.49,0,0,0,.21.4.48.48,0,0,0,.45,0L9,28.68l.35.19.26,1.56a.46.46,0,0,0,.27.35.48.48,0,0,0,.45-.05l1.28-.92.38.12.55,1.47a.47.47,0,0,0,.34.29.46.46,0,0,0,.43-.13l1.08-1.16.39,0,.83,1.34A.46.46,0,0,0,16,32a.47.47,0,0,0,.4-.22l.83-1.34.39,0,1.08,1.16a.46.46,0,0,0,.43.13.47.47,0,0,0,.34-.29L20,29.93l.38-.12,1.28.92a.48.48,0,0,0,.45.05.45.45,0,0,0,.27-.35l.26-1.56.35-.19,1.43.66a.48.48,0,0,0,.45,0,.49.49,0,0,0,.21-.4L25,27.32l.3-.25,1.54.36a.48.48,0,0,0,.44-.12.46.46,0,0,0,.12-.43l-.36-1.54.25-.3,1.58.05a.45.45,0,0,0,.43-.65L28.69,23l.19-.35,1.55-.25a.45.45,0,0,0,.36-.28.43.43,0,0,0-.06-.44l-.92-1.28.12-.39,1.48-.55a.44.44,0,0,0,.29-.34.46.46,0,0,0-.14-.43L30.4,17.62c0-.13,0-.26,0-.39l1.34-.84a.46.46,0,0,0,0-.78Zm-9,11.16A1,1,0,1,1,23.92,26a.95.95,0,0,1-1.14.73Zm-.45-3.09a.87.87,0,0,0-1,.67l-.48,2.22a11.74,11.74,0,0,1-9.75,0l-.48-2.23a.85.85,0,0,0-1-.66l-2,.42a14.67,14.67,0,0,1-1-1.2h9.58c.1,0,.18,0,.18-.12V19.35c0-.1-.08-.12-.18-.12h-2.8V17.08h3a1.9,1.9,0,0,1,1.86,1.62c.12.47.39,2,.57,2.5s.91,1.65,1.69,1.65h4.77l.17,0a11,11,0,0,1-1.08,1.27l-2-.43Zm-13.24,3A.94.94,0,0,1,8,26a1,1,0,1,1,1.13.73ZM5.45,12a1,1,0,0,1-1.74.77,1,1,0,0,1,.49-1.26A1,1,0,0,1,5.45,12ZM4.33,14.66l2.05-.91a.87.87,0,0,0,.44-1.15l-.42-.95H8.06v7.46H4.73a11.37,11.37,0,0,1-.45-3.21,10.41,10.41,0,0,1,.07-1.26Zm9-.73v-2.2h3.95c.2,0,1.44.24,1.44,1.16,0,.77-.95,1-1.73,1H13.32Zm14.34,2q0,.45,0,.87h-1.2c-.12,0-.17.08-.17.2v.55c0,1.3-.73,1.58-1.37,1.65s-1.29-.25-1.37-.63a4.13,4.13,0,0,0-1.91-3.21C22.79,14.59,24,13.49,24,12a3.76,3.76,0,0,0-1.83-3.09,5.22,5.22,0,0,0-2.52-.83H7.25a11.79,11.79,0,0,1,6.54-3.7l1.47,1.54a.87.87,0,0,0,1.22,0l1.64-1.57a11.69,11.69,0,0,1,8,5.72L25,12.64a.87.87,0,0,0,.44,1.14l2.16,1a11.46,11.46,0,0,1,.06,1.17ZM15.25,3.1a1,1,0,0,1,1.34,0,1,1,0,0,1,0,1.35,1,1,0,0,1-1.34,0,1,1,0,0,1,0-1.35Zm11.13,9a.94.94,0,0,1,1.25-.48,1,1,0,1,1-1.25.48Z" fill="currentColor"></path></svg> Rust </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 289"><path fill="#539E43" d="M128 288.464c-3.975 0-7.685-1.06-11.13-2.915l-35.247-20.936c-5.3-2.915-2.65-3.975-1.06-4.505c7.155-2.385 8.48-2.915 15.9-7.156c.796-.53 1.856-.265 2.65.265l27.032 16.166c1.06.53 2.385.53 3.18 0l105.74-61.217c1.06-.53 1.59-1.59 1.59-2.915V83.08c0-1.325-.53-2.385-1.59-2.915l-105.74-60.953c-1.06-.53-2.385-.53-3.18 0L20.405 80.166c-1.06.53-1.59 1.855-1.59 2.915v122.17c0 1.06.53 2.385 1.59 2.915l28.887 16.695c15.636 7.95 25.44-1.325 25.44-10.6V93.68c0-1.59 1.326-3.18 3.181-3.18h13.516c1.59 0 3.18 1.325 3.18 3.18v120.58c0 20.936-11.396 33.126-31.272 33.126c-6.095 0-10.865 0-24.38-6.625l-27.827-15.9C4.24 220.885 0 213.465 0 205.515V83.346C0 75.396 4.24 67.976 11.13 64L116.87 2.783c6.625-3.71 15.635-3.71 22.26 0L244.87 64C251.76 67.975 256 75.395 256 83.346v122.17c0 7.95-4.24 15.37-11.13 19.345L139.13 286.08c-3.445 1.59-7.42 2.385-11.13 2.385Zm32.596-84.009c-46.377 0-55.917-21.2-55.917-39.221c0-1.59 1.325-3.18 3.18-3.18h13.78c1.59 0 2.916 1.06 2.916 2.65c2.12 14.045 8.215 20.936 36.306 20.936c22.261 0 31.802-5.035 31.802-16.96c0-6.891-2.65-11.926-37.367-15.372c-28.886-2.915-46.907-9.275-46.907-32.33c0-21.467 18.02-34.187 48.232-34.187c33.921 0 50.617 11.66 52.737 37.101c0 .795-.265 1.59-.795 2.385c-.53.53-1.325 1.06-2.12 1.06h-13.78c-1.326 0-2.65-1.06-2.916-2.385c-3.18-14.575-11.395-19.345-33.126-19.345c-24.38 0-27.296 8.48-27.296 14.84c0 7.686 3.445 10.07 36.306 14.31c32.597 4.24 47.967 10.336 47.967 33.127c-.265 23.321-19.345 36.571-53.002 36.571Z"></path></svg> Node </div></div> <div class="language-select"> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START -->tokenizer.pre_tokenizer = pre_tokenizer<!-- HTML_TAG_END --></pre></div> </div> <p data-svelte-h="svelte-1hbd718">Of course, if you change the way the pre-tokenizer, you should probably
	retrain your tokenizer from scratch afterward.</p> <h2 class="relative group"><a id="model" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#model"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Model</span></h2> <p data-svelte-h="svelte-1d5s5ai">Once the input texts are normalized and pre-tokenized, the
	<code>Tokenizer</code> applies the model on the
	pre-tokens. This is the part of the pipeline that needs training on your
	corpus (or that has been trained if you are using a pretrained
	tokenizer).</p> <p data-svelte-h="svelte-1776i4x">The role of the model is to split your “words” into tokens, using the
	rules it has learned. It’s also responsible for mapping those tokens to
	their corresponding IDs in the vocabulary of the model.</p> <p data-svelte-h="svelte-1ssp78q">This model is passed along when initializing the
	<code>Tokenizer</code> so you already know how to
	customize this part. Currently, the 🤗 Tokenizers library supports:</p> <ul data-svelte-h="svelte-17p2ane"><li><code>models.BPE</code></li> <li><code>models.Unigram</code></li> <li><code>models.WordLevel</code></li> <li><code>models.WordPiece</code></li></ul> <p data-svelte-h="svelte-vo0orx">For more details about each model and its behavior, you can check
	<a href="components#models">here</a></p> <h2 class="relative group"><a id="post-processing" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#post-processing"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Post-Processing</span></h2> <p data-svelte-h="svelte-bq6cd6">Post-processing is the last step of the tokenization pipeline, to
	perform any additional transformation to the
	<code>Encoding</code> before it’s returned, like
	adding potential special tokens.</p> <p data-svelte-h="svelte-1rbxjab">As we saw in the quick tour, we can customize the post processor of a
	<code>Tokenizer</code> by setting the
	corresponding attribute. For instance, here is how we can post-process
	to make the inputs suitable for the BERT model:</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M15.84.5a16.4,16.4,0,0,0-3.57.32C9.1,1.39,8.53,2.53,8.53,4.64V7.48H16v1H5.77a4.73,4.73,0,0,0-4.7,3.74,14.82,14.82,0,0,0,0,7.54c.57,2.28,1.86,3.82,4,3.82h2.6V20.14a4.73,4.73,0,0,1,4.63-4.63h7.38a3.72,3.72,0,0,0,3.73-3.73V4.64A4.16,4.16,0,0,0,19.65.82,20.49,20.49,0,0,0,15.84.5ZM11.78,2.77a1.39,1.39,0,0,1,1.38,1.46,1.37,1.37,0,0,1-1.38,1.38A1.42,1.42,0,0,1,10.4,4.23,1.44,1.44,0,0,1,11.78,2.77Z" fill="#5a9fd4"></path><path d="M16.16,31.5a16.4,16.4,0,0,0,3.57-.32c3.17-.57,3.74-1.71,3.74-3.82V24.52H16v-1H26.23a4.73,4.73,0,0,0,4.7-3.74,14.82,14.82,0,0,0,0-7.54c-.57-2.28-1.86-3.82-4-3.82h-2.6v3.41a4.73,4.73,0,0,1-4.63,4.63H12.35a3.72,3.72,0,0,0-3.73,3.73v7.14a4.16,4.16,0,0,0,3.73,3.82A20.49,20.49,0,0,0,16.16,31.5Zm4.06-2.27a1.39,1.39,0,0,1-1.38-1.46,1.37,1.37,0,0,1,1.38-1.38,1.42,1.42,0,0,1,1.38,1.38A1.44,1.44,0,0,1,20.22,29.23Z" fill="#ffd43b"></path></svg> Python </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" preserveAspectRatio="xMidYMid meet" width="1em" height="1em" viewBox="0 0 32 32"><path d="M31.77,15.61l-1.34-.83c0-.13,0-.26,0-.39l1.16-1.08a.46.46,0,0,0,.14-.43.44.44,0,0,0-.29-.34L29.92,12l-.12-.38.92-1.28a.46.46,0,0,0,.06-.45.47.47,0,0,0-.36-.28l-1.55-.25L28.68,9l.66-1.44a.48.48,0,0,0,0-.45.46.46,0,0,0-.4-.2L27.32,7l-.25-.3.36-1.54a.46.46,0,0,0-.12-.43.46.46,0,0,0-.43-.13l-1.54.37L25,4.68l.06-1.58a.44.44,0,0,0-.21-.4.45.45,0,0,0-.45,0L23,3.32l-.35-.19L22.4,1.57a.46.46,0,0,0-.28-.35.48.48,0,0,0-.45.05l-1.28.92L20,2.08,19.46.6a.44.44,0,0,0-.34-.29.46.46,0,0,0-.43.14L17.62,1.6l-.39,0L16.39.22a.46.46,0,0,0-.78,0l-.83,1.34-.39,0L13.31.45a.46.46,0,0,0-.43-.14.44.44,0,0,0-.34.29L12,2.08l-.38.11-1.28-.92a.48.48,0,0,0-.45-.05.5.5,0,0,0-.28.35L9.35,3.13,9,3.32,7.57,2.66a.45.45,0,0,0-.45,0,.49.49,0,0,0-.21.4L7,4.68l-.31.25L5.13,4.56a.48.48,0,0,0-.44.13.46.46,0,0,0-.12.43l.36,1.54L4.68,7l-1.58,0a.46.46,0,0,0-.4.2.48.48,0,0,0,0,.45L3.32,9l-.19.35L1.57,9.6a.47.47,0,0,0-.35.28.48.48,0,0,0,.05.45l.92,1.28c0,.12-.07.25-.11.38L.6,12.54a.44.44,0,0,0-.29.34.46.46,0,0,0,.14.43L1.6,14.39l0,.39-1.35.83a.47.47,0,0,0,0,.78l1.35.84,0,.39L.45,18.69a.46.46,0,0,0-.14.43.44.44,0,0,0,.29.34L2.08,20c0,.13.07.26.11.39l-.92,1.28a.46.46,0,0,0-.05.44.45.45,0,0,0,.36.28l1.55.25.19.35-.65,1.44a.45.45,0,0,0,.43.65L4.68,25l.25.3-.36,1.54a.46.46,0,0,0,.12.43.48.48,0,0,0,.44.12l1.54-.36.3.25L6.91,28.9a.49.49,0,0,0,.21.4.48.48,0,0,0,.45,0L9,28.68l.35.19.26,1.56a.46.46,0,0,0,.27.35.48.48,0,0,0,.45-.05l1.28-.92.38.12.55,1.47a.47.47,0,0,0,.34.29.46.46,0,0,0,.43-.13l1.08-1.16.39,0,.83,1.34A.46.46,0,0,0,16,32a.47.47,0,0,0,.4-.22l.83-1.34.39,0,1.08,1.16a.46.46,0,0,0,.43.13.47.47,0,0,0,.34-.29L20,29.93l.38-.12,1.28.92a.48.48,0,0,0,.45.05.45.45,0,0,0,.27-.35l.26-1.56.35-.19,1.43.66a.48.48,0,0,0,.45,0,.49.49,0,0,0,.21-.4L25,27.32l.3-.25,1.54.36a.48.48,0,0,0,.44-.12.46.46,0,0,0,.12-.43l-.36-1.54.25-.3,1.58.05a.45.45,0,0,0,.43-.65L28.69,23l.19-.35,1.55-.25a.45.45,0,0,0,.36-.28.43.43,0,0,0-.06-.44l-.92-1.28.12-.39,1.48-.55a.44.44,0,0,0,.29-.34.46.46,0,0,0-.14-.43L30.4,17.62c0-.13,0-.26,0-.39l1.34-.84a.46.46,0,0,0,0-.78Zm-9,11.16A1,1,0,1,1,23.92,26a.95.95,0,0,1-1.14.73Zm-.45-3.09a.87.87,0,0,0-1,.67l-.48,2.22a11.74,11.74,0,0,1-9.75,0l-.48-2.23a.85.85,0,0,0-1-.66l-2,.42a14.67,14.67,0,0,1-1-1.2h9.58c.1,0,.18,0,.18-.12V19.35c0-.1-.08-.12-.18-.12h-2.8V17.08h3a1.9,1.9,0,0,1,1.86,1.62c.12.47.39,2,.57,2.5s.91,1.65,1.69,1.65h4.77l.17,0a11,11,0,0,1-1.08,1.27l-2-.43Zm-13.24,3A.94.94,0,0,1,8,26a1,1,0,1,1,1.13.73ZM5.45,12a1,1,0,0,1-1.74.77,1,1,0,0,1,.49-1.26A1,1,0,0,1,5.45,12ZM4.33,14.66l2.05-.91a.87.87,0,0,0,.44-1.15l-.42-.95H8.06v7.46H4.73a11.37,11.37,0,0,1-.45-3.21,10.41,10.41,0,0,1,.07-1.26Zm9-.73v-2.2h3.95c.2,0,1.44.24,1.44,1.16,0,.77-.95,1-1.73,1H13.32Zm14.34,2q0,.45,0,.87h-1.2c-.12,0-.17.08-.17.2v.55c0,1.3-.73,1.58-1.37,1.65s-1.29-.25-1.37-.63a4.13,4.13,0,0,0-1.91-3.21C22.79,14.59,24,13.49,24,12a3.76,3.76,0,0,0-1.83-3.09,5.22,5.22,0,0,0-2.52-.83H7.25a11.79,11.79,0,0,1,6.54-3.7l1.47,1.54a.87.87,0,0,0,1.22,0l1.64-1.57a11.69,11.69,0,0,1,8,5.72L25,12.64a.87.87,0,0,0,.44,1.14l2.16,1a11.46,11.46,0,0,1,.06,1.17ZM15.25,3.1a1,1,0,0,1,1.34,0,1,1,0,0,1,0,1.35,1,1,0,0,1-1.34,0,1,1,0,0,1,0-1.35Zm11.13,9a.94.94,0,0,1,1.25-.48,1,1,0,1,1-1.25.48Z" fill="currentColor"></path></svg> Rust </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 289"><path fill="#539E43" d="M128 288.464c-3.975 0-7.685-1.06-11.13-2.915l-35.247-20.936c-5.3-2.915-2.65-3.975-1.06-4.505c7.155-2.385 8.48-2.915 15.9-7.156c.796-.53 1.856-.265 2.65.265l27.032 16.166c1.06.53 2.385.53 3.18 0l105.74-61.217c1.06-.53 1.59-1.59 1.59-2.915V83.08c0-1.325-.53-2.385-1.59-2.915l-105.74-60.953c-1.06-.53-2.385-.53-3.18 0L20.405 80.166c-1.06.53-1.59 1.855-1.59 2.915v122.17c0 1.06.53 2.385 1.59 2.915l28.887 16.695c15.636 7.95 25.44-1.325 25.44-10.6V93.68c0-1.59 1.326-3.18 3.181-3.18h13.516c1.59 0 3.18 1.325 3.18 3.18v120.58c0 20.936-11.396 33.126-31.272 33.126c-6.095 0-10.865 0-24.38-6.625l-27.827-15.9C4.24 220.885 0 213.465 0 205.515V83.346C0 75.396 4.24 67.976 11.13 64L116.87 2.783c6.625-3.71 15.635-3.71 22.26 0L244.87 64C251.76 67.975 256 75.395 256 83.346v122.17c0 7.95-4.24 15.37-11.13 19.345L139.13 286.08c-3.445 1.59-7.42 2.385-11.13 2.385Zm32.596-84.009c-46.377 0-55.917-21.2-55.917-39.221c0-1.59 1.325-3.18 3.18-3.18h13.78c1.59 0 2.916 1.06 2.916 2.65c2.12 14.045 8.215 20.936 36.306 20.936c22.261 0 31.802-5.035 31.802-16.96c0-6.891-2.65-11.926-37.367-15.372c-28.886-2.915-46.907-9.275-46.907-32.33c0-21.467 18.02-34.187 48.232-34.187c33.921 0 50.617 11.66 52.737 37.101c0 .795-.265 1.59-.795 2.385c-.53.53-1.325 1.06-2.12 1.06h-13.78c-1.326 0-2.65-1.06-2.916-2.385c-3.18-14.575-11.395-19.345-33.126-19.345c-24.38 0-27.296 8.48-27.296 14.84c0 7.686 3.445 10.07 36.306 14.31c32.597 4.24 47.967 10.336 47.967 33.127c-.265 23.321-19.345 36.571-53.002 36.571Z"></path></svg> Node </div></div> <div class="language-select"> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START --><span class="hljs-keyword">from</span> tokenizers.processors <span class="hljs-keyword">import</span> TemplateProcessing
	tokenizer.post_processor = TemplateProcessing(
	single=<span class="hljs-string">"[CLS] $A [SEP]"</span>,
	pair=<span class="hljs-string">"[CLS] $A [SEP] $B:1 [SEP]:1"</span>,
	special_tokens=[(<span class="hljs-string">"[CLS]"</span>, <span class="hljs-number">1</span>), (<span class="hljs-string">"[SEP]"</span>, <span class="hljs-number">2</span>)],
	)<!-- HTML_TAG_END --></pre></div> </div> <p data-svelte-h="svelte-1k7gzcb">Note that contrarily to the pre-tokenizer or the normalizer, you don’t
	need to retrain a tokenizer after changing its post-processor.</p> <h2 class="relative group"><a id="all-together-a-bert-tokenizer-from-scratch" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#all-together-a-bert-tokenizer-from-scratch"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>All together: a BERT tokenizer from scratch</span></h2> <p data-svelte-h="svelte-xj0mrt">Let’s put all those pieces together to build a BERT tokenizer. First,
	BERT relies on WordPiece, so we instantiate a new
	<code>Tokenizer</code> with this model:</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M15.84.5a16.4,16.4,0,0,0-3.57.32C9.1,1.39,8.53,2.53,8.53,4.64V7.48H16v1H5.77a4.73,4.73,0,0,0-4.7,3.74,14.82,14.82,0,0,0,0,7.54c.57,2.28,1.86,3.82,4,3.82h2.6V20.14a4.73,4.73,0,0,1,4.63-4.63h7.38a3.72,3.72,0,0,0,3.73-3.73V4.64A4.16,4.16,0,0,0,19.65.82,20.49,20.49,0,0,0,15.84.5ZM11.78,2.77a1.39,1.39,0,0,1,1.38,1.46,1.37,1.37,0,0,1-1.38,1.38A1.42,1.42,0,0,1,10.4,4.23,1.44,1.44,0,0,1,11.78,2.77Z" fill="#5a9fd4"></path><path d="M16.16,31.5a16.4,16.4,0,0,0,3.57-.32c3.17-.57,3.74-1.71,3.74-3.82V24.52H16v-1H26.23a4.73,4.73,0,0,0,4.7-3.74,14.82,14.82,0,0,0,0-7.54c-.57-2.28-1.86-3.82-4-3.82h-2.6v3.41a4.73,4.73,0,0,1-4.63,4.63H12.35a3.72,3.72,0,0,0-3.73,3.73v7.14a4.16,4.16,0,0,0,3.73,3.82A20.49,20.49,0,0,0,16.16,31.5Zm4.06-2.27a1.39,1.39,0,0,1-1.38-1.46,1.37,1.37,0,0,1,1.38-1.38,1.42,1.42,0,0,1,1.38,1.38A1.44,1.44,0,0,1,20.22,29.23Z" fill="#ffd43b"></path></svg> Python </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" preserveAspectRatio="xMidYMid meet" width="1em" height="1em" viewBox="0 0 32 32"><path d="M31.77,15.61l-1.34-.83c0-.13,0-.26,0-.39l1.16-1.08a.46.46,0,0,0,.14-.43.44.44,0,0,0-.29-.34L29.92,12l-.12-.38.92-1.28a.46.46,0,0,0,.06-.45.47.47,0,0,0-.36-.28l-1.55-.25L28.68,9l.66-1.44a.48.48,0,0,0,0-.45.46.46,0,0,0-.4-.2L27.32,7l-.25-.3.36-1.54a.46.46,0,0,0-.12-.43.46.46,0,0,0-.43-.13l-1.54.37L25,4.68l.06-1.58a.44.44,0,0,0-.21-.4.45.45,0,0,0-.45,0L23,3.32l-.35-.19L22.4,1.57a.46.46,0,0,0-.28-.35.48.48,0,0,0-.45.05l-1.28.92L20,2.08,19.46.6a.44.44,0,0,0-.34-.29.46.46,0,0,0-.43.14L17.62,1.6l-.39,0L16.39.22a.46.46,0,0,0-.78,0l-.83,1.34-.39,0L13.31.45a.46.46,0,0,0-.43-.14.44.44,0,0,0-.34.29L12,2.08l-.38.11-1.28-.92a.48.48,0,0,0-.45-.05.5.5,0,0,0-.28.35L9.35,3.13,9,3.32,7.57,2.66a.45.45,0,0,0-.45,0,.49.49,0,0,0-.21.4L7,4.68l-.31.25L5.13,4.56a.48.48,0,0,0-.44.13.46.46,0,0,0-.12.43l.36,1.54L4.68,7l-1.58,0a.46.46,0,0,0-.4.2.48.48,0,0,0,0,.45L3.32,9l-.19.35L1.57,9.6a.47.47,0,0,0-.35.28.48.48,0,0,0,.05.45l.92,1.28c0,.12-.07.25-.11.38L.6,12.54a.44.44,0,0,0-.29.34.46.46,0,0,0,.14.43L1.6,14.39l0,.39-1.35.83a.47.47,0,0,0,0,.78l1.35.84,0,.39L.45,18.69a.46.46,0,0,0-.14.43.44.44,0,0,0,.29.34L2.08,20c0,.13.07.26.11.39l-.92,1.28a.46.46,0,0,0-.05.44.45.45,0,0,0,.36.28l1.55.25.19.35-.65,1.44a.45.45,0,0,0,.43.65L4.68,25l.25.3-.36,1.54a.46.46,0,0,0,.12.43.48.48,0,0,0,.44.12l1.54-.36.3.25L6.91,28.9a.49.49,0,0,0,.21.4.48.48,0,0,0,.45,0L9,28.68l.35.19.26,1.56a.46.46,0,0,0,.27.35.48.48,0,0,0,.45-.05l1.28-.92.38.12.55,1.47a.47.47,0,0,0,.34.29.46.46,0,0,0,.43-.13l1.08-1.16.39,0,.83,1.34A.46.46,0,0,0,16,32a.47.47,0,0,0,.4-.22l.83-1.34.39,0,1.08,1.16a.46.46,0,0,0,.43.13.47.47,0,0,0,.34-.29L20,29.93l.38-.12,1.28.92a.48.48,0,0,0,.45.05.45.45,0,0,0,.27-.35l.26-1.56.35-.19,1.43.66a.48.48,0,0,0,.45,0,.49.49,0,0,0,.21-.4L25,27.32l.3-.25,1.54.36a.48.48,0,0,0,.44-.12.46.46,0,0,0,.12-.43l-.36-1.54.25-.3,1.58.05a.45.45,0,0,0,.43-.65L28.69,23l.19-.35,1.55-.25a.45.45,0,0,0,.36-.28.43.43,0,0,0-.06-.44l-.92-1.28.12-.39,1.48-.55a.44.44,0,0,0,.29-.34.46.46,0,0,0-.14-.43L30.4,17.62c0-.13,0-.26,0-.39l1.34-.84a.46.46,0,0,0,0-.78Zm-9,11.16A1,1,0,1,1,23.92,26a.95.95,0,0,1-1.14.73Zm-.45-3.09a.87.87,0,0,0-1,.67l-.48,2.22a11.74,11.74,0,0,1-9.75,0l-.48-2.23a.85.85,0,0,0-1-.66l-2,.42a14.67,14.67,0,0,1-1-1.2h9.58c.1,0,.18,0,.18-.12V19.35c0-.1-.08-.12-.18-.12h-2.8V17.08h3a1.9,1.9,0,0,1,1.86,1.62c.12.47.39,2,.57,2.5s.91,1.65,1.69,1.65h4.77l.17,0a11,11,0,0,1-1.08,1.27l-2-.43Zm-13.24,3A.94.94,0,0,1,8,26a1,1,0,1,1,1.13.73ZM5.45,12a1,1,0,0,1-1.74.77,1,1,0,0,1,.49-1.26A1,1,0,0,1,5.45,12ZM4.33,14.66l2.05-.91a.87.87,0,0,0,.44-1.15l-.42-.95H8.06v7.46H4.73a11.37,11.37,0,0,1-.45-3.21,10.41,10.41,0,0,1,.07-1.26Zm9-.73v-2.2h3.95c.2,0,1.44.24,1.44,1.16,0,.77-.95,1-1.73,1H13.32Zm14.34,2q0,.45,0,.87h-1.2c-.12,0-.17.08-.17.2v.55c0,1.3-.73,1.58-1.37,1.65s-1.29-.25-1.37-.63a4.13,4.13,0,0,0-1.91-3.21C22.79,14.59,24,13.49,24,12a3.76,3.76,0,0,0-1.83-3.09,5.22,5.22,0,0,0-2.52-.83H7.25a11.79,11.79,0,0,1,6.54-3.7l1.47,1.54a.87.87,0,0,0,1.22,0l1.64-1.57a11.69,11.69,0,0,1,8,5.72L25,12.64a.87.87,0,0,0,.44,1.14l2.16,1a11.46,11.46,0,0,1,.06,1.17ZM15.25,3.1a1,1,0,0,1,1.34,0,1,1,0,0,1,0,1.35,1,1,0,0,1-1.34,0,1,1,0,0,1,0-1.35Zm11.13,9a.94.94,0,0,1,1.25-.48,1,1,0,1,1-1.25.48Z" fill="currentColor"></path></svg> Rust </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 289"><path fill="#539E43" d="M128 288.464c-3.975 0-7.685-1.06-11.13-2.915l-35.247-20.936c-5.3-2.915-2.65-3.975-1.06-4.505c7.155-2.385 8.48-2.915 15.9-7.156c.796-.53 1.856-.265 2.65.265l27.032 16.166c1.06.53 2.385.53 3.18 0l105.74-61.217c1.06-.53 1.59-1.59 1.59-2.915V83.08c0-1.325-.53-2.385-1.59-2.915l-105.74-60.953c-1.06-.53-2.385-.53-3.18 0L20.405 80.166c-1.06.53-1.59 1.855-1.59 2.915v122.17c0 1.06.53 2.385 1.59 2.915l28.887 16.695c15.636 7.95 25.44-1.325 25.44-10.6V93.68c0-1.59 1.326-3.18 3.181-3.18h13.516c1.59 0 3.18 1.325 3.18 3.18v120.58c0 20.936-11.396 33.126-31.272 33.126c-6.095 0-10.865 0-24.38-6.625l-27.827-15.9C4.24 220.885 0 213.465 0 205.515V83.346C0 75.396 4.24 67.976 11.13 64L116.87 2.783c6.625-3.71 15.635-3.71 22.26 0L244.87 64C251.76 67.975 256 75.395 256 83.346v122.17c0 7.95-4.24 15.37-11.13 19.345L139.13 286.08c-3.445 1.59-7.42 2.385-11.13 2.385Zm32.596-84.009c-46.377 0-55.917-21.2-55.917-39.221c0-1.59 1.325-3.18 3.18-3.18h13.78c1.59 0 2.916 1.06 2.916 2.65c2.12 14.045 8.215 20.936 36.306 20.936c22.261 0 31.802-5.035 31.802-16.96c0-6.891-2.65-11.926-37.367-15.372c-28.886-2.915-46.907-9.275-46.907-32.33c0-21.467 18.02-34.187 48.232-34.187c33.921 0 50.617 11.66 52.737 37.101c0 .795-.265 1.59-.795 2.385c-.53.53-1.325 1.06-2.12 1.06h-13.78c-1.326 0-2.65-1.06-2.916-2.385c-3.18-14.575-11.395-19.345-33.126-19.345c-24.38 0-27.296 8.48-27.296 14.84c0 7.686 3.445 10.07 36.306 14.31c32.597 4.24 47.967 10.336 47.967 33.127c-.265 23.321-19.345 36.571-53.002 36.571Z"></path></svg> Node </div></div> <div class="language-select"> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START --><span class="hljs-keyword">from</span> tokenizers <span class="hljs-keyword">import</span> Tokenizer
	<span class="hljs-keyword">from</span> tokenizers.models <span class="hljs-keyword">import</span> WordPiece
	bert_tokenizer = Tokenizer(WordPiece(unk_token=<span class="hljs-string">"[UNK]"</span>))<!-- HTML_TAG_END --></pre></div> </div> <p data-svelte-h="svelte-15y7mhn">Then we know that BERT preprocesses texts by removing accents and
	lowercasing. We also use a unicode normalizer:</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M15.84.5a16.4,16.4,0,0,0-3.57.32C9.1,1.39,8.53,2.53,8.53,4.64V7.48H16v1H5.77a4.73,4.73,0,0,0-4.7,3.74,14.82,14.82,0,0,0,0,7.54c.57,2.28,1.86,3.82,4,3.82h2.6V20.14a4.73,4.73,0,0,1,4.63-4.63h7.38a3.72,3.72,0,0,0,3.73-3.73V4.64A4.16,4.16,0,0,0,19.65.82,20.49,20.49,0,0,0,15.84.5ZM11.78,2.77a1.39,1.39,0,0,1,1.38,1.46,1.37,1.37,0,0,1-1.38,1.38A1.42,1.42,0,0,1,10.4,4.23,1.44,1.44,0,0,1,11.78,2.77Z" fill="#5a9fd4"></path><path d="M16.16,31.5a16.4,16.4,0,0,0,3.57-.32c3.17-.57,3.74-1.71,3.74-3.82V24.52H16v-1H26.23a4.73,4.73,0,0,0,4.7-3.74,14.82,14.82,0,0,0,0-7.54c-.57-2.28-1.86-3.82-4-3.82h-2.6v3.41a4.73,4.73,0,0,1-4.63,4.63H12.35a3.72,3.72,0,0,0-3.73,3.73v7.14a4.16,4.16,0,0,0,3.73,3.82A20.49,20.49,0,0,0,16.16,31.5Zm4.06-2.27a1.39,1.39,0,0,1-1.38-1.46,1.37,1.37,0,0,1,1.38-1.38,1.42,1.42,0,0,1,1.38,1.38A1.44,1.44,0,0,1,20.22,29.23Z" fill="#ffd43b"></path></svg> Python </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" preserveAspectRatio="xMidYMid meet" width="1em" height="1em" viewBox="0 0 32 32"><path d="M31.77,15.61l-1.34-.83c0-.13,0-.26,0-.39l1.16-1.08a.46.46,0,0,0,.14-.43.44.44,0,0,0-.29-.34L29.92,12l-.12-.38.92-1.28a.46.46,0,0,0,.06-.45.47.47,0,0,0-.36-.28l-1.55-.25L28.68,9l.66-1.44a.48.48,0,0,0,0-.45.46.46,0,0,0-.4-.2L27.32,7l-.25-.3.36-1.54a.46.46,0,0,0-.12-.43.46.46,0,0,0-.43-.13l-1.54.37L25,4.68l.06-1.58a.44.44,0,0,0-.21-.4.45.45,0,0,0-.45,0L23,3.32l-.35-.19L22.4,1.57a.46.46,0,0,0-.28-.35.48.48,0,0,0-.45.05l-1.28.92L20,2.08,19.46.6a.44.44,0,0,0-.34-.29.46.46,0,0,0-.43.14L17.62,1.6l-.39,0L16.39.22a.46.46,0,0,0-.78,0l-.83,1.34-.39,0L13.31.45a.46.46,0,0,0-.43-.14.44.44,0,0,0-.34.29L12,2.08l-.38.11-1.28-.92a.48.48,0,0,0-.45-.05.5.5,0,0,0-.28.35L9.35,3.13,9,3.32,7.57,2.66a.45.45,0,0,0-.45,0,.49.49,0,0,0-.21.4L7,4.68l-.31.25L5.13,4.56a.48.48,0,0,0-.44.13.46.46,0,0,0-.12.43l.36,1.54L4.68,7l-1.58,0a.46.46,0,0,0-.4.2.48.48,0,0,0,0,.45L3.32,9l-.19.35L1.57,9.6a.47.47,0,0,0-.35.28.48.48,0,0,0,.05.45l.92,1.28c0,.12-.07.25-.11.38L.6,12.54a.44.44,0,0,0-.29.34.46.46,0,0,0,.14.43L1.6,14.39l0,.39-1.35.83a.47.47,0,0,0,0,.78l1.35.84,0,.39L.45,18.69a.46.46,0,0,0-.14.43.44.44,0,0,0,.29.34L2.08,20c0,.13.07.26.11.39l-.92,1.28a.46.46,0,0,0-.05.44.45.45,0,0,0,.36.28l1.55.25.19.35-.65,1.44a.45.45,0,0,0,.43.65L4.68,25l.25.3-.36,1.54a.46.46,0,0,0,.12.43.48.48,0,0,0,.44.12l1.54-.36.3.25L6.91,28.9a.49.49,0,0,0,.21.4.48.48,0,0,0,.45,0L9,28.68l.35.19.26,1.56a.46.46,0,0,0,.27.35.48.48,0,0,0,.45-.05l1.28-.92.38.12.55,1.47a.47.47,0,0,0,.34.29.46.46,0,0,0,.43-.13l1.08-1.16.39,0,.83,1.34A.46.46,0,0,0,16,32a.47.47,0,0,0,.4-.22l.83-1.34.39,0,1.08,1.16a.46.46,0,0,0,.43.13.47.47,0,0,0,.34-.29L20,29.93l.38-.12,1.28.92a.48.48,0,0,0,.45.05.45.45,0,0,0,.27-.35l.26-1.56.35-.19,1.43.66a.48.48,0,0,0,.45,0,.49.49,0,0,0,.21-.4L25,27.32l.3-.25,1.54.36a.48.48,0,0,0,.44-.12.46.46,0,0,0,.12-.43l-.36-1.54.25-.3,1.58.05a.45.45,0,0,0,.43-.65L28.69,23l.19-.35,1.55-.25a.45.45,0,0,0,.36-.28.43.43,0,0,0-.06-.44l-.92-1.28.12-.39,1.48-.55a.44.44,0,0,0,.29-.34.46.46,0,0,0-.14-.43L30.4,17.62c0-.13,0-.26,0-.39l1.34-.84a.46.46,0,0,0,0-.78Zm-9,11.16A1,1,0,1,1,23.92,26a.95.95,0,0,1-1.14.73Zm-.45-3.09a.87.87,0,0,0-1,.67l-.48,2.22a11.74,11.74,0,0,1-9.75,0l-.48-2.23a.85.85,0,0,0-1-.66l-2,.42a14.67,14.67,0,0,1-1-1.2h9.58c.1,0,.18,0,.18-.12V19.35c0-.1-.08-.12-.18-.12h-2.8V17.08h3a1.9,1.9,0,0,1,1.86,1.62c.12.47.39,2,.57,2.5s.91,1.65,1.69,1.65h4.77l.17,0a11,11,0,0,1-1.08,1.27l-2-.43Zm-13.24,3A.94.94,0,0,1,8,26a1,1,0,1,1,1.13.73ZM5.45,12a1,1,0,0,1-1.74.77,1,1,0,0,1,.49-1.26A1,1,0,0,1,5.45,12ZM4.33,14.66l2.05-.91a.87.87,0,0,0,.44-1.15l-.42-.95H8.06v7.46H4.73a11.37,11.37,0,0,1-.45-3.21,10.41,10.41,0,0,1,.07-1.26Zm9-.73v-2.2h3.95c.2,0,1.44.24,1.44,1.16,0,.77-.95,1-1.73,1H13.32Zm14.34,2q0,.45,0,.87h-1.2c-.12,0-.17.08-.17.2v.55c0,1.3-.73,1.58-1.37,1.65s-1.29-.25-1.37-.63a4.13,4.13,0,0,0-1.91-3.21C22.79,14.59,24,13.49,24,12a3.76,3.76,0,0,0-1.83-3.09,5.22,5.22,0,0,0-2.52-.83H7.25a11.79,11.79,0,0,1,6.54-3.7l1.47,1.54a.87.87,0,0,0,1.22,0l1.64-1.57a11.69,11.69,0,0,1,8,5.72L25,12.64a.87.87,0,0,0,.44,1.14l2.16,1a11.46,11.46,0,0,1,.06,1.17ZM15.25,3.1a1,1,0,0,1,1.34,0,1,1,0,0,1,0,1.35,1,1,0,0,1-1.34,0,1,1,0,0,1,0-1.35Zm11.13,9a.94.94,0,0,1,1.25-.48,1,1,0,1,1-1.25.48Z" fill="currentColor"></path></svg> Rust </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 289"><path fill="#539E43" d="M128 288.464c-3.975 0-7.685-1.06-11.13-2.915l-35.247-20.936c-5.3-2.915-2.65-3.975-1.06-4.505c7.155-2.385 8.48-2.915 15.9-7.156c.796-.53 1.856-.265 2.65.265l27.032 16.166c1.06.53 2.385.53 3.18 0l105.74-61.217c1.06-.53 1.59-1.59 1.59-2.915V83.08c0-1.325-.53-2.385-1.59-2.915l-105.74-60.953c-1.06-.53-2.385-.53-3.18 0L20.405 80.166c-1.06.53-1.59 1.855-1.59 2.915v122.17c0 1.06.53 2.385 1.59 2.915l28.887 16.695c15.636 7.95 25.44-1.325 25.44-10.6V93.68c0-1.59 1.326-3.18 3.181-3.18h13.516c1.59 0 3.18 1.325 3.18 3.18v120.58c0 20.936-11.396 33.126-31.272 33.126c-6.095 0-10.865 0-24.38-6.625l-27.827-15.9C4.24 220.885 0 213.465 0 205.515V83.346C0 75.396 4.24 67.976 11.13 64L116.87 2.783c6.625-3.71 15.635-3.71 22.26 0L244.87 64C251.76 67.975 256 75.395 256 83.346v122.17c0 7.95-4.24 15.37-11.13 19.345L139.13 286.08c-3.445 1.59-7.42 2.385-11.13 2.385Zm32.596-84.009c-46.377 0-55.917-21.2-55.917-39.221c0-1.59 1.325-3.18 3.18-3.18h13.78c1.59 0 2.916 1.06 2.916 2.65c2.12 14.045 8.215 20.936 36.306 20.936c22.261 0 31.802-5.035 31.802-16.96c0-6.891-2.65-11.926-37.367-15.372c-28.886-2.915-46.907-9.275-46.907-32.33c0-21.467 18.02-34.187 48.232-34.187c33.921 0 50.617 11.66 52.737 37.101c0 .795-.265 1.59-.795 2.385c-.53.53-1.325 1.06-2.12 1.06h-13.78c-1.326 0-2.65-1.06-2.916-2.385c-3.18-14.575-11.395-19.345-33.126-19.345c-24.38 0-27.296 8.48-27.296 14.84c0 7.686 3.445 10.07 36.306 14.31c32.597 4.24 47.967 10.336 47.967 33.127c-.265 23.321-19.345 36.571-53.002 36.571Z"></path></svg> Node </div></div> <div class="language-select"> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START --><span class="hljs-keyword">from</span> tokenizers <span class="hljs-keyword">import</span> normalizers
	<span class="hljs-keyword">from</span> tokenizers.normalizers <span class="hljs-keyword">import</span> NFD, Lowercase, StripAccents
	bert_tokenizer.normalizer = normalizers.<span class="hljs-type">Sequence</span>([NFD(), Lowercase(), StripAccents()])<!-- HTML_TAG_END --></pre></div> </div> <p data-svelte-h="svelte-ifp6a5">The pre-tokenizer is just splitting on whitespace and punctuation:</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M15.84.5a16.4,16.4,0,0,0-3.57.32C9.1,1.39,8.53,2.53,8.53,4.64V7.48H16v1H5.77a4.73,4.73,0,0,0-4.7,3.74,14.82,14.82,0,0,0,0,7.54c.57,2.28,1.86,3.82,4,3.82h2.6V20.14a4.73,4.73,0,0,1,4.63-4.63h7.38a3.72,3.72,0,0,0,3.73-3.73V4.64A4.16,4.16,0,0,0,19.65.82,20.49,20.49,0,0,0,15.84.5ZM11.78,2.77a1.39,1.39,0,0,1,1.38,1.46,1.37,1.37,0,0,1-1.38,1.38A1.42,1.42,0,0,1,10.4,4.23,1.44,1.44,0,0,1,11.78,2.77Z" fill="#5a9fd4"></path><path d="M16.16,31.5a16.4,16.4,0,0,0,3.57-.32c3.17-.57,3.74-1.71,3.74-3.82V24.52H16v-1H26.23a4.73,4.73,0,0,0,4.7-3.74,14.82,14.82,0,0,0,0-7.54c-.57-2.28-1.86-3.82-4-3.82h-2.6v3.41a4.73,4.73,0,0,1-4.63,4.63H12.35a3.72,3.72,0,0,0-3.73,3.73v7.14a4.16,4.16,0,0,0,3.73,3.82A20.49,20.49,0,0,0,16.16,31.5Zm4.06-2.27a1.39,1.39,0,0,1-1.38-1.46,1.37,1.37,0,0,1,1.38-1.38,1.42,1.42,0,0,1,1.38,1.38A1.44,1.44,0,0,1,20.22,29.23Z" fill="#ffd43b"></path></svg> Python </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" preserveAspectRatio="xMidYMid meet" width="1em" height="1em" viewBox="0 0 32 32"><path 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fill="currentColor"></path></svg> Rust </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 289"><path fill="#539E43" d="M128 288.464c-3.975 0-7.685-1.06-11.13-2.915l-35.247-20.936c-5.3-2.915-2.65-3.975-1.06-4.505c7.155-2.385 8.48-2.915 15.9-7.156c.796-.53 1.856-.265 2.65.265l27.032 16.166c1.06.53 2.385.53 3.18 0l105.74-61.217c1.06-.53 1.59-1.59 1.59-2.915V83.08c0-1.325-.53-2.385-1.59-2.915l-105.74-60.953c-1.06-.53-2.385-.53-3.18 0L20.405 80.166c-1.06.53-1.59 1.855-1.59 2.915v122.17c0 1.06.53 2.385 1.59 2.915l28.887 16.695c15.636 7.95 25.44-1.325 25.44-10.6V93.68c0-1.59 1.326-3.18 3.181-3.18h13.516c1.59 0 3.18 1.325 3.18 3.18v120.58c0 20.936-11.396 33.126-31.272 33.126c-6.095 0-10.865 0-24.38-6.625l-27.827-15.9C4.24 220.885 0 213.465 0 205.515V83.346C0 75.396 4.24 67.976 11.13 64L116.87 2.783c6.625-3.71 15.635-3.71 22.26 0L244.87 64C251.76 67.975 256 75.395 256 83.346v122.17c0 7.95-4.24 15.37-11.13 19.345L139.13 286.08c-3.445 1.59-7.42 2.385-11.13 2.385Zm32.596-84.009c-46.377 0-55.917-21.2-55.917-39.221c0-1.59 1.325-3.18 3.18-3.18h13.78c1.59 0 2.916 1.06 2.916 2.65c2.12 14.045 8.215 20.936 36.306 20.936c22.261 0 31.802-5.035 31.802-16.96c0-6.891-2.65-11.926-37.367-15.372c-28.886-2.915-46.907-9.275-46.907-32.33c0-21.467 18.02-34.187 48.232-34.187c33.921 0 50.617 11.66 52.737 37.101c0 .795-.265 1.59-.795 2.385c-.53.53-1.325 1.06-2.12 1.06h-13.78c-1.326 0-2.65-1.06-2.916-2.385c-3.18-14.575-11.395-19.345-33.126-19.345c-24.38 0-27.296 8.48-27.296 14.84c0 7.686 3.445 10.07 36.306 14.31c32.597 4.24 47.967 10.336 47.967 33.127c-.265 23.321-19.345 36.571-53.002 36.571Z"></path></svg> Node </div></div> <div class="language-select"> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START --><span class="hljs-keyword">from</span> tokenizers.pre_tokenizers <span class="hljs-keyword">import</span> Whitespace
	bert_tokenizer.pre_tokenizer = Whitespace()<!-- HTML_TAG_END --></pre></div> </div> <p data-svelte-h="svelte-1jpbo92">And the post-processing uses the template we saw in the previous
	section:</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M15.84.5a16.4,16.4,0,0,0-3.57.32C9.1,1.39,8.53,2.53,8.53,4.64V7.48H16v1H5.77a4.73,4.73,0,0,0-4.7,3.74,14.82,14.82,0,0,0,0,7.54c.57,2.28,1.86,3.82,4,3.82h2.6V20.14a4.73,4.73,0,0,1,4.63-4.63h7.38a3.72,3.72,0,0,0,3.73-3.73V4.64A4.16,4.16,0,0,0,19.65.82,20.49,20.49,0,0,0,15.84.5ZM11.78,2.77a1.39,1.39,0,0,1,1.38,1.46,1.37,1.37,0,0,1-1.38,1.38A1.42,1.42,0,0,1,10.4,4.23,1.44,1.44,0,0,1,11.78,2.77Z" fill="#5a9fd4"></path><path d="M16.16,31.5a16.4,16.4,0,0,0,3.57-.32c3.17-.57,3.74-1.71,3.74-3.82V24.52H16v-1H26.23a4.73,4.73,0,0,0,4.7-3.74,14.82,14.82,0,0,0,0-7.54c-.57-2.28-1.86-3.82-4-3.82h-2.6v3.41a4.73,4.73,0,0,1-4.63,4.63H12.35a3.72,3.72,0,0,0-3.73,3.73v7.14a4.16,4.16,0,0,0,3.73,3.82A20.49,20.49,0,0,0,16.16,31.5Zm4.06-2.27a1.39,1.39,0,0,1-1.38-1.46,1.37,1.37,0,0,1,1.38-1.38,1.42,1.42,0,0,1,1.38,1.38A1.44,1.44,0,0,1,20.22,29.23Z" fill="#ffd43b"></path></svg> Python </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" preserveAspectRatio="xMidYMid meet" width="1em" height="1em" viewBox="0 0 32 32"><path d="M31.77,15.61l-1.34-.83c0-.13,0-.26,0-.39l1.16-1.08a.46.46,0,0,0,.14-.43.44.44,0,0,0-.29-.34L29.92,12l-.12-.38.92-1.28a.46.46,0,0,0,.06-.45.47.47,0,0,0-.36-.28l-1.55-.25L28.68,9l.66-1.44a.48.48,0,0,0,0-.45.46.46,0,0,0-.4-.2L27.32,7l-.25-.3.36-1.54a.46.46,0,0,0-.12-.43.46.46,0,0,0-.43-.13l-1.54.37L25,4.68l.06-1.58a.44.44,0,0,0-.21-.4.45.45,0,0,0-.45,0L23,3.32l-.35-.19L22.4,1.57a.46.46,0,0,0-.28-.35.48.48,0,0,0-.45.05l-1.28.92L20,2.08,19.46.6a.44.44,0,0,0-.34-.29.46.46,0,0,0-.43.14L17.62,1.6l-.39,0L16.39.22a.46.46,0,0,0-.78,0l-.83,1.34-.39,0L13.31.45a.46.46,0,0,0-.43-.14.44.44,0,0,0-.34.29L12,2.08l-.38.11-1.28-.92a.48.48,0,0,0-.45-.05.5.5,0,0,0-.28.35L9.35,3.13,9,3.32,7.57,2.66a.45.45,0,0,0-.45,0,.49.49,0,0,0-.21.4L7,4.68l-.31.25L5.13,4.56a.48.48,0,0,0-.44.13.46.46,0,0,0-.12.43l.36,1.54L4.68,7l-1.58,0a.46.46,0,0,0-.4.2.48.48,0,0,0,0,.45L3.32,9l-.19.35L1.57,9.6a.47.47,0,0,0-.35.28.48.48,0,0,0,.05.45l.92,1.28c0,.12-.07.25-.11.38L.6,12.54a.44.44,0,0,0-.29.34.46.46,0,0,0,.14.43L1.6,14.39l0,.39-1.35.83a.47.47,0,0,0,0,.78l1.35.84,0,.39L.45,18.69a.46.46,0,0,0-.14.43.44.44,0,0,0,.29.34L2.08,20c0,.13.07.26.11.39l-.92,1.28a.46.46,0,0,0-.05.44.45.45,0,0,0,.36.28l1.55.25.19.35-.65,1.44a.45.45,0,0,0,.43.65L4.68,25l.25.3-.36,1.54a.46.46,0,0,0,.12.43.48.48,0,0,0,.44.12l1.54-.36.3.25L6.91,28.9a.49.49,0,0,0,.21.4.48.48,0,0,0,.45,0L9,28.68l.35.19.26,1.56a.46.46,0,0,0,.27.35.48.48,0,0,0,.45-.05l1.28-.92.38.12.55,1.47a.47.47,0,0,0,.34.29.46.46,0,0,0,.43-.13l1.08-1.16.39,0,.83,1.34A.46.46,0,0,0,16,32a.47.47,0,0,0,.4-.22l.83-1.34.39,0,1.08,1.16a.46.46,0,0,0,.43.13.47.47,0,0,0,.34-.29L20,29.93l.38-.12,1.28.92a.48.48,0,0,0,.45.05.45.45,0,0,0,.27-.35l.26-1.56.35-.19,1.43.66a.48.48,0,0,0,.45,0,.49.49,0,0,0,.21-.4L25,27.32l.3-.25,1.54.36a.48.48,0,0,0,.44-.12.46.46,0,0,0,.12-.43l-.36-1.54.25-.3,1.58.05a.45.45,0,0,0,.43-.65L28.69,23l.19-.35,1.55-.25a.45.45,0,0,0,.36-.28.43.43,0,0,0-.06-.44l-.92-1.28.12-.39,1.48-.55a.44.44,0,0,0,.29-.34.46.46,0,0,0-.14-.43L30.4,17.62c0-.13,0-.26,0-.39l1.34-.84a.46.46,0,0,0,0-.78Zm-9,11.16A1,1,0,1,1,23.92,26a.95.95,0,0,1-1.14.73Zm-.45-3.09a.87.87,0,0,0-1,.67l-.48,2.22a11.74,11.74,0,0,1-9.75,0l-.48-2.23a.85.85,0,0,0-1-.66l-2,.42a14.67,14.67,0,0,1-1-1.2h9.58c.1,0,.18,0,.18-.12V19.35c0-.1-.08-.12-.18-.12h-2.8V17.08h3a1.9,1.9,0,0,1,1.86,1.62c.12.47.39,2,.57,2.5s.91,1.65,1.69,1.65h4.77l.17,0a11,11,0,0,1-1.08,1.27l-2-.43Zm-13.24,3A.94.94,0,0,1,8,26a1,1,0,1,1,1.13.73ZM5.45,12a1,1,0,0,1-1.74.77,1,1,0,0,1,.49-1.26A1,1,0,0,1,5.45,12ZM4.33,14.66l2.05-.91a.87.87,0,0,0,.44-1.15l-.42-.95H8.06v7.46H4.73a11.37,11.37,0,0,1-.45-3.21,10.41,10.41,0,0,1,.07-1.26Zm9-.73v-2.2h3.95c.2,0,1.44.24,1.44,1.16,0,.77-.95,1-1.73,1H13.32Zm14.34,2q0,.45,0,.87h-1.2c-.12,0-.17.08-.17.2v.55c0,1.3-.73,1.58-1.37,1.65s-1.29-.25-1.37-.63a4.13,4.13,0,0,0-1.91-3.21C22.79,14.59,24,13.49,24,12a3.76,3.76,0,0,0-1.83-3.09,5.22,5.22,0,0,0-2.52-.83H7.25a11.79,11.79,0,0,1,6.54-3.7l1.47,1.54a.87.87,0,0,0,1.22,0l1.64-1.57a11.69,11.69,0,0,1,8,5.72L25,12.64a.87.87,0,0,0,.44,1.14l2.16,1a11.46,11.46,0,0,1,.06,1.17ZM15.25,3.1a1,1,0,0,1,1.34,0,1,1,0,0,1,0,1.35,1,1,0,0,1-1.34,0,1,1,0,0,1,0-1.35Zm11.13,9a.94.94,0,0,1,1.25-.48,1,1,0,1,1-1.25.48Z" fill="currentColor"></path></svg> Rust </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 289"><path fill="#539E43" d="M128 288.464c-3.975 0-7.685-1.06-11.13-2.915l-35.247-20.936c-5.3-2.915-2.65-3.975-1.06-4.505c7.155-2.385 8.48-2.915 15.9-7.156c.796-.53 1.856-.265 2.65.265l27.032 16.166c1.06.53 2.385.53 3.18 0l105.74-61.217c1.06-.53 1.59-1.59 1.59-2.915V83.08c0-1.325-.53-2.385-1.59-2.915l-105.74-60.953c-1.06-.53-2.385-.53-3.18 0L20.405 80.166c-1.06.53-1.59 1.855-1.59 2.915v122.17c0 1.06.53 2.385 1.59 2.915l28.887 16.695c15.636 7.95 25.44-1.325 25.44-10.6V93.68c0-1.59 1.326-3.18 3.181-3.18h13.516c1.59 0 3.18 1.325 3.18 3.18v120.58c0 20.936-11.396 33.126-31.272 33.126c-6.095 0-10.865 0-24.38-6.625l-27.827-15.9C4.24 220.885 0 213.465 0 205.515V83.346C0 75.396 4.24 67.976 11.13 64L116.87 2.783c6.625-3.71 15.635-3.71 22.26 0L244.87 64C251.76 67.975 256 75.395 256 83.346v122.17c0 7.95-4.24 15.37-11.13 19.345L139.13 286.08c-3.445 1.59-7.42 2.385-11.13 2.385Zm32.596-84.009c-46.377 0-55.917-21.2-55.917-39.221c0-1.59 1.325-3.18 3.18-3.18h13.78c1.59 0 2.916 1.06 2.916 2.65c2.12 14.045 8.215 20.936 36.306 20.936c22.261 0 31.802-5.035 31.802-16.96c0-6.891-2.65-11.926-37.367-15.372c-28.886-2.915-46.907-9.275-46.907-32.33c0-21.467 18.02-34.187 48.232-34.187c33.921 0 50.617 11.66 52.737 37.101c0 .795-.265 1.59-.795 2.385c-.53.53-1.325 1.06-2.12 1.06h-13.78c-1.326 0-2.65-1.06-2.916-2.385c-3.18-14.575-11.395-19.345-33.126-19.345c-24.38 0-27.296 8.48-27.296 14.84c0 7.686 3.445 10.07 36.306 14.31c32.597 4.24 47.967 10.336 47.967 33.127c-.265 23.321-19.345 36.571-53.002 36.571Z"></path></svg> Node </div></div> <div class="language-select"> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START --><span class="hljs-keyword">from</span> tokenizers.processors <span class="hljs-keyword">import</span> TemplateProcessing
	bert_tokenizer.post_processor = TemplateProcessing(
	single=<span class="hljs-string">"[CLS] $A [SEP]"</span>,
	pair=<span class="hljs-string">"[CLS] $A [SEP] $B:1 [SEP]:1"</span>,
	special_tokens=[
	(<span class="hljs-string">"[CLS]"</span>, <span class="hljs-number">1</span>),
	(<span class="hljs-string">"[SEP]"</span>, <span class="hljs-number">2</span>),
	],
	)<!-- HTML_TAG_END --></pre></div> </div> <p data-svelte-h="svelte-v2snrq">We can use this tokenizer and train on it on wikitext like in the
	<code>quicktour</code>:</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M15.84.5a16.4,16.4,0,0,0-3.57.32C9.1,1.39,8.53,2.53,8.53,4.64V7.48H16v1H5.77a4.73,4.73,0,0,0-4.7,3.74,14.82,14.82,0,0,0,0,7.54c.57,2.28,1.86,3.82,4,3.82h2.6V20.14a4.73,4.73,0,0,1,4.63-4.63h7.38a3.72,3.72,0,0,0,3.73-3.73V4.64A4.16,4.16,0,0,0,19.65.82,20.49,20.49,0,0,0,15.84.5ZM11.78,2.77a1.39,1.39,0,0,1,1.38,1.46,1.37,1.37,0,0,1-1.38,1.38A1.42,1.42,0,0,1,10.4,4.23,1.44,1.44,0,0,1,11.78,2.77Z" fill="#5a9fd4"></path><path d="M16.16,31.5a16.4,16.4,0,0,0,3.57-.32c3.17-.57,3.74-1.71,3.74-3.82V24.52H16v-1H26.23a4.73,4.73,0,0,0,4.7-3.74,14.82,14.82,0,0,0,0-7.54c-.57-2.28-1.86-3.82-4-3.82h-2.6v3.41a4.73,4.73,0,0,1-4.63,4.63H12.35a3.72,3.72,0,0,0-3.73,3.73v7.14a4.16,4.16,0,0,0,3.73,3.82A20.49,20.49,0,0,0,16.16,31.5Zm4.06-2.27a1.39,1.39,0,0,1-1.38-1.46,1.37,1.37,0,0,1,1.38-1.38,1.42,1.42,0,0,1,1.38,1.38A1.44,1.44,0,0,1,20.22,29.23Z" fill="#ffd43b"></path></svg> Python </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" preserveAspectRatio="xMidYMid meet" width="1em" height="1em" viewBox="0 0 32 32"><path d="M31.77,15.61l-1.34-.83c0-.13,0-.26,0-.39l1.16-1.08a.46.46,0,0,0,.14-.43.44.44,0,0,0-.29-.34L29.92,12l-.12-.38.92-1.28a.46.46,0,0,0,.06-.45.47.47,0,0,0-.36-.28l-1.55-.25L28.68,9l.66-1.44a.48.48,0,0,0,0-.45.46.46,0,0,0-.4-.2L27.32,7l-.25-.3.36-1.54a.46.46,0,0,0-.12-.43.46.46,0,0,0-.43-.13l-1.54.37L25,4.68l.06-1.58a.44.44,0,0,0-.21-.4.45.45,0,0,0-.45,0L23,3.32l-.35-.19L22.4,1.57a.46.46,0,0,0-.28-.35.48.48,0,0,0-.45.05l-1.28.92L20,2.08,19.46.6a.44.44,0,0,0-.34-.29.46.46,0,0,0-.43.14L17.62,1.6l-.39,0L16.39.22a.46.46,0,0,0-.78,0l-.83,1.34-.39,0L13.31.45a.46.46,0,0,0-.43-.14.44.44,0,0,0-.34.29L12,2.08l-.38.11-1.28-.92a.48.48,0,0,0-.45-.05.5.5,0,0,0-.28.35L9.35,3.13,9,3.32,7.57,2.66a.45.45,0,0,0-.45,0,.49.49,0,0,0-.21.4L7,4.68l-.31.25L5.13,4.56a.48.48,0,0,0-.44.13.46.46,0,0,0-.12.43l.36,1.54L4.68,7l-1.58,0a.46.46,0,0,0-.4.2.48.48,0,0,0,0,.45L3.32,9l-.19.35L1.57,9.6a.47.47,0,0,0-.35.28.48.48,0,0,0,.05.45l.92,1.28c0,.12-.07.25-.11.38L.6,12.54a.44.44,0,0,0-.29.34.46.46,0,0,0,.14.43L1.6,14.39l0,.39-1.35.83a.47.47,0,0,0,0,.78l1.35.84,0,.39L.45,18.69a.46.46,0,0,0-.14.43.44.44,0,0,0,.29.34L2.08,20c0,.13.07.26.11.39l-.92,1.28a.46.46,0,0,0-.05.44.45.45,0,0,0,.36.28l1.55.25.19.35-.65,1.44a.45.45,0,0,0,.43.65L4.68,25l.25.3-.36,1.54a.46.46,0,0,0,.12.43.48.48,0,0,0,.44.12l1.54-.36.3.25L6.91,28.9a.49.49,0,0,0,.21.4.48.48,0,0,0,.45,0L9,28.68l.35.19.26,1.56a.46.46,0,0,0,.27.35.48.48,0,0,0,.45-.05l1.28-.92.38.12.55,1.47a.47.47,0,0,0,.34.29.46.46,0,0,0,.43-.13l1.08-1.16.39,0,.83,1.34A.46.46,0,0,0,16,32a.47.47,0,0,0,.4-.22l.83-1.34.39,0,1.08,1.16a.46.46,0,0,0,.43.13.47.47,0,0,0,.34-.29L20,29.93l.38-.12,1.28.92a.48.48,0,0,0,.45.05.45.45,0,0,0,.27-.35l.26-1.56.35-.19,1.43.66a.48.48,0,0,0,.45,0,.49.49,0,0,0,.21-.4L25,27.32l.3-.25,1.54.36a.48.48,0,0,0,.44-.12.46.46,0,0,0,.12-.43l-.36-1.54.25-.3,1.58.05a.45.45,0,0,0,.43-.65L28.69,23l.19-.35,1.55-.25a.45.45,0,0,0,.36-.28.43.43,0,0,0-.06-.44l-.92-1.28.12-.39,1.48-.55a.44.44,0,0,0,.29-.34.46.46,0,0,0-.14-.43L30.4,17.62c0-.13,0-.26,0-.39l1.34-.84a.46.46,0,0,0,0-.78Zm-9,11.16A1,1,0,1,1,23.92,26a.95.95,0,0,1-1.14.73Zm-.45-3.09a.87.87,0,0,0-1,.67l-.48,2.22a11.74,11.74,0,0,1-9.75,0l-.48-2.23a.85.85,0,0,0-1-.66l-2,.42a14.67,14.67,0,0,1-1-1.2h9.58c.1,0,.18,0,.18-.12V19.35c0-.1-.08-.12-.18-.12h-2.8V17.08h3a1.9,1.9,0,0,1,1.86,1.62c.12.47.39,2,.57,2.5s.91,1.65,1.69,1.65h4.77l.17,0a11,11,0,0,1-1.08,1.27l-2-.43Zm-13.24,3A.94.94,0,0,1,8,26a1,1,0,1,1,1.13.73ZM5.45,12a1,1,0,0,1-1.74.77,1,1,0,0,1,.49-1.26A1,1,0,0,1,5.45,12ZM4.33,14.66l2.05-.91a.87.87,0,0,0,.44-1.15l-.42-.95H8.06v7.46H4.73a11.37,11.37,0,0,1-.45-3.21,10.41,10.41,0,0,1,.07-1.26Zm9-.73v-2.2h3.95c.2,0,1.44.24,1.44,1.16,0,.77-.95,1-1.73,1H13.32Zm14.34,2q0,.45,0,.87h-1.2c-.12,0-.17.08-.17.2v.55c0,1.3-.73,1.58-1.37,1.65s-1.29-.25-1.37-.63a4.13,4.13,0,0,0-1.91-3.21C22.79,14.59,24,13.49,24,12a3.76,3.76,0,0,0-1.83-3.09,5.22,5.22,0,0,0-2.52-.83H7.25a11.79,11.79,0,0,1,6.54-3.7l1.47,1.54a.87.87,0,0,0,1.22,0l1.64-1.57a11.69,11.69,0,0,1,8,5.72L25,12.64a.87.87,0,0,0,.44,1.14l2.16,1a11.46,11.46,0,0,1,.06,1.17ZM15.25,3.1a1,1,0,0,1,1.34,0,1,1,0,0,1,0,1.35,1,1,0,0,1-1.34,0,1,1,0,0,1,0-1.35Zm11.13,9a.94.94,0,0,1,1.25-.48,1,1,0,1,1-1.25.48Z" fill="currentColor"></path></svg> Rust </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 289"><path fill="#539E43" d="M128 288.464c-3.975 0-7.685-1.06-11.13-2.915l-35.247-20.936c-5.3-2.915-2.65-3.975-1.06-4.505c7.155-2.385 8.48-2.915 15.9-7.156c.796-.53 1.856-.265 2.65.265l27.032 16.166c1.06.53 2.385.53 3.18 0l105.74-61.217c1.06-.53 1.59-1.59 1.59-2.915V83.08c0-1.325-.53-2.385-1.59-2.915l-105.74-60.953c-1.06-.53-2.385-.53-3.18 0L20.405 80.166c-1.06.53-1.59 1.855-1.59 2.915v122.17c0 1.06.53 2.385 1.59 2.915l28.887 16.695c15.636 7.95 25.44-1.325 25.44-10.6V93.68c0-1.59 1.326-3.18 3.181-3.18h13.516c1.59 0 3.18 1.325 3.18 3.18v120.58c0 20.936-11.396 33.126-31.272 33.126c-6.095 0-10.865 0-24.38-6.625l-27.827-15.9C4.24 220.885 0 213.465 0 205.515V83.346C0 75.396 4.24 67.976 11.13 64L116.87 2.783c6.625-3.71 15.635-3.71 22.26 0L244.87 64C251.76 67.975 256 75.395 256 83.346v122.17c0 7.95-4.24 15.37-11.13 19.345L139.13 286.08c-3.445 1.59-7.42 2.385-11.13 2.385Zm32.596-84.009c-46.377 0-55.917-21.2-55.917-39.221c0-1.59 1.325-3.18 3.18-3.18h13.78c1.59 0 2.916 1.06 2.916 2.65c2.12 14.045 8.215 20.936 36.306 20.936c22.261 0 31.802-5.035 31.802-16.96c0-6.891-2.65-11.926-37.367-15.372c-28.886-2.915-46.907-9.275-46.907-32.33c0-21.467 18.02-34.187 48.232-34.187c33.921 0 50.617 11.66 52.737 37.101c0 .795-.265 1.59-.795 2.385c-.53.53-1.325 1.06-2.12 1.06h-13.78c-1.326 0-2.65-1.06-2.916-2.385c-3.18-14.575-11.395-19.345-33.126-19.345c-24.38 0-27.296 8.48-27.296 14.84c0 7.686 3.445 10.07 36.306 14.31c32.597 4.24 47.967 10.336 47.967 33.127c-.265 23.321-19.345 36.571-53.002 36.571Z"></path></svg> Node </div></div> <div class="language-select"> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START --><span class="hljs-keyword">from</span> tokenizers.trainers <span class="hljs-keyword">import</span> WordPieceTrainer
	trainer = WordPieceTrainer(vocab_size=<span class="hljs-number">30522</span>, special_tokens=[<span class="hljs-string">"[UNK]"</span>, <span class="hljs-string">"[CLS]"</span>, <span class="hljs-string">"[SEP]"</span>, <span class="hljs-string">"[PAD]"</span>, <span class="hljs-string">"[MASK]"</span>])
	files = [<span class="hljs-string">f"data/wikitext-103-raw/wiki.<span class="hljs-subst">{split}</span>.raw"</span> <span class="hljs-keyword">for</span> split <span class="hljs-keyword">in</span> [<span class="hljs-string">"test"</span>, <span class="hljs-string">"train"</span>, <span class="hljs-string">"valid"</span>]]
	bert_tokenizer.train(files, trainer)
	bert_tokenizer.save(<span class="hljs-string">"data/bert-wiki.json"</span>)<!-- HTML_TAG_END --></pre></div> </div> <h2 class="relative group"><a id="decoding" class="header-link block pr-1.5 text-lg no-hover:hidden with-hover:absolute with-hover:p-1.5 with-hover:opacity-0 with-hover:group-hover:opacity-100 with-hover:right-full" href="#decoding"><span><svg class="" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 256"><path d="M167.594 88.393a8.001 8.001 0 0 1 0 11.314l-67.882 67.882a8 8 0 1 1-11.314-11.315l67.882-67.881a8.003 8.003 0 0 1 11.314 0zm-28.287 84.86l-28.284 28.284a40 40 0 0 1-56.567-56.567l28.284-28.284a8 8 0 0 0-11.315-11.315l-28.284 28.284a56 56 0 0 0 79.196 79.197l28.285-28.285a8 8 0 1 0-11.315-11.314zM212.852 43.14a56.002 56.002 0 0 0-79.196 0l-28.284 28.284a8 8 0 1 0 11.314 11.314l28.284-28.284a40 40 0 0 1 56.568 56.567l-28.285 28.285a8 8 0 0 0 11.315 11.314l28.284-28.284a56.065 56.065 0 0 0 0-79.196z" fill="currentColor"></path></svg></span></a> <span>Decoding</span></h2> <p data-svelte-h="svelte-ppu6m1">On top of encoding the input texts, a <code>Tokenizer</code> also has an API for decoding, that is converting IDs
	generated by your model back to a text. This is done by the methods
	<code>Tokenizer.decode</code> (for one predicted text) and <code>Tokenizer.decode_batch</code> (for a batch of predictions).</p> <p data-svelte-h="svelte-16ah0w1">The <code>decoder</code> will first convert the IDs back to tokens
	(using the tokenizer’s vocabulary) and remove all special tokens, then
	join those tokens with spaces:</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M15.84.5a16.4,16.4,0,0,0-3.57.32C9.1,1.39,8.53,2.53,8.53,4.64V7.48H16v1H5.77a4.73,4.73,0,0,0-4.7,3.74,14.82,14.82,0,0,0,0,7.54c.57,2.28,1.86,3.82,4,3.82h2.6V20.14a4.73,4.73,0,0,1,4.63-4.63h7.38a3.72,3.72,0,0,0,3.73-3.73V4.64A4.16,4.16,0,0,0,19.65.82,20.49,20.49,0,0,0,15.84.5ZM11.78,2.77a1.39,1.39,0,0,1,1.38,1.46,1.37,1.37,0,0,1-1.38,1.38A1.42,1.42,0,0,1,10.4,4.23,1.44,1.44,0,0,1,11.78,2.77Z" fill="#5a9fd4"></path><path d="M16.16,31.5a16.4,16.4,0,0,0,3.57-.32c3.17-.57,3.74-1.71,3.74-3.82V24.52H16v-1H26.23a4.73,4.73,0,0,0,4.7-3.74,14.82,14.82,0,0,0,0-7.54c-.57-2.28-1.86-3.82-4-3.82h-2.6v3.41a4.73,4.73,0,0,1-4.63,4.63H12.35a3.72,3.72,0,0,0-3.73,3.73v7.14a4.16,4.16,0,0,0,3.73,3.82A20.49,20.49,0,0,0,16.16,31.5Zm4.06-2.27a1.39,1.39,0,0,1-1.38-1.46,1.37,1.37,0,0,1,1.38-1.38,1.42,1.42,0,0,1,1.38,1.38A1.44,1.44,0,0,1,20.22,29.23Z" fill="#ffd43b"></path></svg> Python </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" preserveAspectRatio="xMidYMid meet" width="1em" height="1em" viewBox="0 0 32 32"><path d="M31.77,15.61l-1.34-.83c0-.13,0-.26,0-.39l1.16-1.08a.46.46,0,0,0,.14-.43.44.44,0,0,0-.29-.34L29.92,12l-.12-.38.92-1.28a.46.46,0,0,0,.06-.45.47.47,0,0,0-.36-.28l-1.55-.25L28.68,9l.66-1.44a.48.48,0,0,0,0-.45.46.46,0,0,0-.4-.2L27.32,7l-.25-.3.36-1.54a.46.46,0,0,0-.12-.43.46.46,0,0,0-.43-.13l-1.54.37L25,4.68l.06-1.58a.44.44,0,0,0-.21-.4.45.45,0,0,0-.45,0L23,3.32l-.35-.19L22.4,1.57a.46.46,0,0,0-.28-.35.48.48,0,0,0-.45.05l-1.28.92L20,2.08,19.46.6a.44.44,0,0,0-.34-.29.46.46,0,0,0-.43.14L17.62,1.6l-.39,0L16.39.22a.46.46,0,0,0-.78,0l-.83,1.34-.39,0L13.31.45a.46.46,0,0,0-.43-.14.44.44,0,0,0-.34.29L12,2.08l-.38.11-1.28-.92a.48.48,0,0,0-.45-.05.5.5,0,0,0-.28.35L9.35,3.13,9,3.32,7.57,2.66a.45.45,0,0,0-.45,0,.49.49,0,0,0-.21.4L7,4.68l-.31.25L5.13,4.56a.48.48,0,0,0-.44.13.46.46,0,0,0-.12.43l.36,1.54L4.68,7l-1.58,0a.46.46,0,0,0-.4.2.48.48,0,0,0,0,.45L3.32,9l-.19.35L1.57,9.6a.47.47,0,0,0-.35.28.48.48,0,0,0,.05.45l.92,1.28c0,.12-.07.25-.11.38L.6,12.54a.44.44,0,0,0-.29.34.46.46,0,0,0,.14.43L1.6,14.39l0,.39-1.35.83a.47.47,0,0,0,0,.78l1.35.84,0,.39L.45,18.69a.46.46,0,0,0-.14.43.44.44,0,0,0,.29.34L2.08,20c0,.13.07.26.11.39l-.92,1.28a.46.46,0,0,0-.05.44.45.45,0,0,0,.36.28l1.55.25.19.35-.65,1.44a.45.45,0,0,0,.43.65L4.68,25l.25.3-.36,1.54a.46.46,0,0,0,.12.43.48.48,0,0,0,.44.12l1.54-.36.3.25L6.91,28.9a.49.49,0,0,0,.21.4.48.48,0,0,0,.45,0L9,28.68l.35.19.26,1.56a.46.46,0,0,0,.27.35.48.48,0,0,0,.45-.05l1.28-.92.38.12.55,1.47a.47.47,0,0,0,.34.29.46.46,0,0,0,.43-.13l1.08-1.16.39,0,.83,1.34A.46.46,0,0,0,16,32a.47.47,0,0,0,.4-.22l.83-1.34.39,0,1.08,1.16a.46.46,0,0,0,.43.13.47.47,0,0,0,.34-.29L20,29.93l.38-.12,1.28.92a.48.48,0,0,0,.45.05.45.45,0,0,0,.27-.35l.26-1.56.35-.19,1.43.66a.48.48,0,0,0,.45,0,.49.49,0,0,0,.21-.4L25,27.32l.3-.25,1.54.36a.48.48,0,0,0,.44-.12.46.46,0,0,0,.12-.43l-.36-1.54.25-.3,1.58.05a.45.45,0,0,0,.43-.65L28.69,23l.19-.35,1.55-.25a.45.45,0,0,0,.36-.28.43.43,0,0,0-.06-.44l-.92-1.28.12-.39,1.48-.55a.44.44,0,0,0,.29-.34.46.46,0,0,0-.14-.43L30.4,17.62c0-.13,0-.26,0-.39l1.34-.84a.46.46,0,0,0,0-.78Zm-9,11.16A1,1,0,1,1,23.92,26a.95.95,0,0,1-1.14.73Zm-.45-3.09a.87.87,0,0,0-1,.67l-.48,2.22a11.74,11.74,0,0,1-9.75,0l-.48-2.23a.85.85,0,0,0-1-.66l-2,.42a14.67,14.67,0,0,1-1-1.2h9.58c.1,0,.18,0,.18-.12V19.35c0-.1-.08-.12-.18-.12h-2.8V17.08h3a1.9,1.9,0,0,1,1.86,1.62c.12.47.39,2,.57,2.5s.91,1.65,1.69,1.65h4.77l.17,0a11,11,0,0,1-1.08,1.27l-2-.43Zm-13.24,3A.94.94,0,0,1,8,26a1,1,0,1,1,1.13.73ZM5.45,12a1,1,0,0,1-1.74.77,1,1,0,0,1,.49-1.26A1,1,0,0,1,5.45,12ZM4.33,14.66l2.05-.91a.87.87,0,0,0,.44-1.15l-.42-.95H8.06v7.46H4.73a11.37,11.37,0,0,1-.45-3.21,10.41,10.41,0,0,1,.07-1.26Zm9-.73v-2.2h3.95c.2,0,1.44.24,1.44,1.16,0,.77-.95,1-1.73,1H13.32Zm14.34,2q0,.45,0,.87h-1.2c-.12,0-.17.08-.17.2v.55c0,1.3-.73,1.58-1.37,1.65s-1.29-.25-1.37-.63a4.13,4.13,0,0,0-1.91-3.21C22.79,14.59,24,13.49,24,12a3.76,3.76,0,0,0-1.83-3.09,5.22,5.22,0,0,0-2.52-.83H7.25a11.79,11.79,0,0,1,6.54-3.7l1.47,1.54a.87.87,0,0,0,1.22,0l1.64-1.57a11.69,11.69,0,0,1,8,5.72L25,12.64a.87.87,0,0,0,.44,1.14l2.16,1a11.46,11.46,0,0,1,.06,1.17ZM15.25,3.1a1,1,0,0,1,1.34,0,1,1,0,0,1,0,1.35,1,1,0,0,1-1.34,0,1,1,0,0,1,0-1.35Zm11.13,9a.94.94,0,0,1,1.25-.48,1,1,0,1,1-1.25.48Z" fill="currentColor"></path></svg> Rust </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 289"><path fill="#539E43" d="M128 288.464c-3.975 0-7.685-1.06-11.13-2.915l-35.247-20.936c-5.3-2.915-2.65-3.975-1.06-4.505c7.155-2.385 8.48-2.915 15.9-7.156c.796-.53 1.856-.265 2.65.265l27.032 16.166c1.06.53 2.385.53 3.18 0l105.74-61.217c1.06-.53 1.59-1.59 1.59-2.915V83.08c0-1.325-.53-2.385-1.59-2.915l-105.74-60.953c-1.06-.53-2.385-.53-3.18 0L20.405 80.166c-1.06.53-1.59 1.855-1.59 2.915v122.17c0 1.06.53 2.385 1.59 2.915l28.887 16.695c15.636 7.95 25.44-1.325 25.44-10.6V93.68c0-1.59 1.326-3.18 3.181-3.18h13.516c1.59 0 3.18 1.325 3.18 3.18v120.58c0 20.936-11.396 33.126-31.272 33.126c-6.095 0-10.865 0-24.38-6.625l-27.827-15.9C4.24 220.885 0 213.465 0 205.515V83.346C0 75.396 4.24 67.976 11.13 64L116.87 2.783c6.625-3.71 15.635-3.71 22.26 0L244.87 64C251.76 67.975 256 75.395 256 83.346v122.17c0 7.95-4.24 15.37-11.13 19.345L139.13 286.08c-3.445 1.59-7.42 2.385-11.13 2.385Zm32.596-84.009c-46.377 0-55.917-21.2-55.917-39.221c0-1.59 1.325-3.18 3.18-3.18h13.78c1.59 0 2.916 1.06 2.916 2.65c2.12 14.045 8.215 20.936 36.306 20.936c22.261 0 31.802-5.035 31.802-16.96c0-6.891-2.65-11.926-37.367-15.372c-28.886-2.915-46.907-9.275-46.907-32.33c0-21.467 18.02-34.187 48.232-34.187c33.921 0 50.617 11.66 52.737 37.101c0 .795-.265 1.59-.795 2.385c-.53.53-1.325 1.06-2.12 1.06h-13.78c-1.326 0-2.65-1.06-2.916-2.385c-3.18-14.575-11.395-19.345-33.126-19.345c-24.38 0-27.296 8.48-27.296 14.84c0 7.686 3.445 10.07 36.306 14.31c32.597 4.24 47.967 10.336 47.967 33.127c-.265 23.321-19.345 36.571-53.002 36.571Z"></path></svg> Node </div></div> <div class="language-select"> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START -->output = tokenizer.encode(<span class="hljs-string">"Hello, y'all! How are you 😁 ?"</span>)
	<span class="hljs-built_in">print</span>(output.ids)
	<span class="hljs-comment"># [1, 27253, 16, 93, 11, 5097, 5, 7961, 5112, 6218, 0, 35, 2]</span>
	tokenizer.decode([<span class="hljs-number">1</span>, <span class="hljs-number">27253</span>, <span class="hljs-number">16</span>, <span class="hljs-number">93</span>, <span class="hljs-number">11</span>, <span class="hljs-number">5097</span>, <span class="hljs-number">5</span>, <span class="hljs-number">7961</span>, <span class="hljs-number">5112</span>, <span class="hljs-number">6218</span>, <span class="hljs-number">0</span>, <span class="hljs-number">35</span>, <span class="hljs-number">2</span>])
	<span class="hljs-comment"># "Hello , y ' all ! How are you ?"</span><!-- HTML_TAG_END --></pre></div> </div> <p data-svelte-h="svelte-19gaglf">If you used a model that added special characters to represent subtokens
	of a given “word” (like the <code>"##"</code> in
	WordPiece) you will need to customize the <code>decoder</code> to treat
	them properly. If we take our previous <code>bert_tokenizer</code> for instance the
	default decoding will give:</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M15.84.5a16.4,16.4,0,0,0-3.57.32C9.1,1.39,8.53,2.53,8.53,4.64V7.48H16v1H5.77a4.73,4.73,0,0,0-4.7,3.74,14.82,14.82,0,0,0,0,7.54c.57,2.28,1.86,3.82,4,3.82h2.6V20.14a4.73,4.73,0,0,1,4.63-4.63h7.38a3.72,3.72,0,0,0,3.73-3.73V4.64A4.16,4.16,0,0,0,19.65.82,20.49,20.49,0,0,0,15.84.5ZM11.78,2.77a1.39,1.39,0,0,1,1.38,1.46,1.37,1.37,0,0,1-1.38,1.38A1.42,1.42,0,0,1,10.4,4.23,1.44,1.44,0,0,1,11.78,2.77Z" fill="#5a9fd4"></path><path d="M16.16,31.5a16.4,16.4,0,0,0,3.57-.32c3.17-.57,3.74-1.71,3.74-3.82V24.52H16v-1H26.23a4.73,4.73,0,0,0,4.7-3.74,14.82,14.82,0,0,0,0-7.54c-.57-2.28-1.86-3.82-4-3.82h-2.6v3.41a4.73,4.73,0,0,1-4.63,4.63H12.35a3.72,3.72,0,0,0-3.73,3.73v7.14a4.16,4.16,0,0,0,3.73,3.82A20.49,20.49,0,0,0,16.16,31.5Zm4.06-2.27a1.39,1.39,0,0,1-1.38-1.46,1.37,1.37,0,0,1,1.38-1.38,1.42,1.42,0,0,1,1.38,1.38A1.44,1.44,0,0,1,20.22,29.23Z" fill="#ffd43b"></path></svg> Python </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" preserveAspectRatio="xMidYMid meet" width="1em" height="1em" viewBox="0 0 32 32"><path d="M31.77,15.61l-1.34-.83c0-.13,0-.26,0-.39l1.16-1.08a.46.46,0,0,0,.14-.43.44.44,0,0,0-.29-.34L29.92,12l-.12-.38.92-1.28a.46.46,0,0,0,.06-.45.47.47,0,0,0-.36-.28l-1.55-.25L28.68,9l.66-1.44a.48.48,0,0,0,0-.45.46.46,0,0,0-.4-.2L27.32,7l-.25-.3.36-1.54a.46.46,0,0,0-.12-.43.46.46,0,0,0-.43-.13l-1.54.37L25,4.68l.06-1.58a.44.44,0,0,0-.21-.4.45.45,0,0,0-.45,0L23,3.32l-.35-.19L22.4,1.57a.46.46,0,0,0-.28-.35.48.48,0,0,0-.45.05l-1.28.92L20,2.08,19.46.6a.44.44,0,0,0-.34-.29.46.46,0,0,0-.43.14L17.62,1.6l-.39,0L16.39.22a.46.46,0,0,0-.78,0l-.83,1.34-.39,0L13.31.45a.46.46,0,0,0-.43-.14.44.44,0,0,0-.34.29L12,2.08l-.38.11-1.28-.92a.48.48,0,0,0-.45-.05.5.5,0,0,0-.28.35L9.35,3.13,9,3.32,7.57,2.66a.45.45,0,0,0-.45,0,.49.49,0,0,0-.21.4L7,4.68l-.31.25L5.13,4.56a.48.48,0,0,0-.44.13.46.46,0,0,0-.12.43l.36,1.54L4.68,7l-1.58,0a.46.46,0,0,0-.4.2.48.48,0,0,0,0,.45L3.32,9l-.19.35L1.57,9.6a.47.47,0,0,0-.35.28.48.48,0,0,0,.05.45l.92,1.28c0,.12-.07.25-.11.38L.6,12.54a.44.44,0,0,0-.29.34.46.46,0,0,0,.14.43L1.6,14.39l0,.39-1.35.83a.47.47,0,0,0,0,.78l1.35.84,0,.39L.45,18.69a.46.46,0,0,0-.14.43.44.44,0,0,0,.29.34L2.08,20c0,.13.07.26.11.39l-.92,1.28a.46.46,0,0,0-.05.44.45.45,0,0,0,.36.28l1.55.25.19.35-.65,1.44a.45.45,0,0,0,.43.65L4.68,25l.25.3-.36,1.54a.46.46,0,0,0,.12.43.48.48,0,0,0,.44.12l1.54-.36.3.25L6.91,28.9a.49.49,0,0,0,.21.4.48.48,0,0,0,.45,0L9,28.68l.35.19.26,1.56a.46.46,0,0,0,.27.35.48.48,0,0,0,.45-.05l1.28-.92.38.12.55,1.47a.47.47,0,0,0,.34.29.46.46,0,0,0,.43-.13l1.08-1.16.39,0,.83,1.34A.46.46,0,0,0,16,32a.47.47,0,0,0,.4-.22l.83-1.34.39,0,1.08,1.16a.46.46,0,0,0,.43.13.47.47,0,0,0,.34-.29L20,29.93l.38-.12,1.28.92a.48.48,0,0,0,.45.05.45.45,0,0,0,.27-.35l.26-1.56.35-.19,1.43.66a.48.48,0,0,0,.45,0,.49.49,0,0,0,.21-.4L25,27.32l.3-.25,1.54.36a.48.48,0,0,0,.44-.12.46.46,0,0,0,.12-.43l-.36-1.54.25-.3,1.58.05a.45.45,0,0,0,.43-.65L28.69,23l.19-.35,1.55-.25a.45.45,0,0,0,.36-.28.43.43,0,0,0-.06-.44l-.92-1.28.12-.39,1.48-.55a.44.44,0,0,0,.29-.34.46.46,0,0,0-.14-.43L30.4,17.62c0-.13,0-.26,0-.39l1.34-.84a.46.46,0,0,0,0-.78Zm-9,11.16A1,1,0,1,1,23.92,26a.95.95,0,0,1-1.14.73Zm-.45-3.09a.87.87,0,0,0-1,.67l-.48,2.22a11.74,11.74,0,0,1-9.75,0l-.48-2.23a.85.85,0,0,0-1-.66l-2,.42a14.67,14.67,0,0,1-1-1.2h9.58c.1,0,.18,0,.18-.12V19.35c0-.1-.08-.12-.18-.12h-2.8V17.08h3a1.9,1.9,0,0,1,1.86,1.62c.12.47.39,2,.57,2.5s.91,1.65,1.69,1.65h4.77l.17,0a11,11,0,0,1-1.08,1.27l-2-.43Zm-13.24,3A.94.94,0,0,1,8,26a1,1,0,1,1,1.13.73ZM5.45,12a1,1,0,0,1-1.74.77,1,1,0,0,1,.49-1.26A1,1,0,0,1,5.45,12ZM4.33,14.66l2.05-.91a.87.87,0,0,0,.44-1.15l-.42-.95H8.06v7.46H4.73a11.37,11.37,0,0,1-.45-3.21,10.41,10.41,0,0,1,.07-1.26Zm9-.73v-2.2h3.95c.2,0,1.44.24,1.44,1.16,0,.77-.95,1-1.73,1H13.32Zm14.34,2q0,.45,0,.87h-1.2c-.12,0-.17.08-.17.2v.55c0,1.3-.73,1.58-1.37,1.65s-1.29-.25-1.37-.63a4.13,4.13,0,0,0-1.91-3.21C22.79,14.59,24,13.49,24,12a3.76,3.76,0,0,0-1.83-3.09,5.22,5.22,0,0,0-2.52-.83H7.25a11.79,11.79,0,0,1,6.54-3.7l1.47,1.54a.87.87,0,0,0,1.22,0l1.64-1.57a11.69,11.69,0,0,1,8,5.72L25,12.64a.87.87,0,0,0,.44,1.14l2.16,1a11.46,11.46,0,0,1,.06,1.17ZM15.25,3.1a1,1,0,0,1,1.34,0,1,1,0,0,1,0,1.35,1,1,0,0,1-1.34,0,1,1,0,0,1,0-1.35Zm11.13,9a.94.94,0,0,1,1.25-.48,1,1,0,1,1-1.25.48Z" fill="currentColor"></path></svg> Rust </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 289"><path fill="#539E43" d="M128 288.464c-3.975 0-7.685-1.06-11.13-2.915l-35.247-20.936c-5.3-2.915-2.65-3.975-1.06-4.505c7.155-2.385 8.48-2.915 15.9-7.156c.796-.53 1.856-.265 2.65.265l27.032 16.166c1.06.53 2.385.53 3.18 0l105.74-61.217c1.06-.53 1.59-1.59 1.59-2.915V83.08c0-1.325-.53-2.385-1.59-2.915l-105.74-60.953c-1.06-.53-2.385-.53-3.18 0L20.405 80.166c-1.06.53-1.59 1.855-1.59 2.915v122.17c0 1.06.53 2.385 1.59 2.915l28.887 16.695c15.636 7.95 25.44-1.325 25.44-10.6V93.68c0-1.59 1.326-3.18 3.181-3.18h13.516c1.59 0 3.18 1.325 3.18 3.18v120.58c0 20.936-11.396 33.126-31.272 33.126c-6.095 0-10.865 0-24.38-6.625l-27.827-15.9C4.24 220.885 0 213.465 0 205.515V83.346C0 75.396 4.24 67.976 11.13 64L116.87 2.783c6.625-3.71 15.635-3.71 22.26 0L244.87 64C251.76 67.975 256 75.395 256 83.346v122.17c0 7.95-4.24 15.37-11.13 19.345L139.13 286.08c-3.445 1.59-7.42 2.385-11.13 2.385Zm32.596-84.009c-46.377 0-55.917-21.2-55.917-39.221c0-1.59 1.325-3.18 3.18-3.18h13.78c1.59 0 2.916 1.06 2.916 2.65c2.12 14.045 8.215 20.936 36.306 20.936c22.261 0 31.802-5.035 31.802-16.96c0-6.891-2.65-11.926-37.367-15.372c-28.886-2.915-46.907-9.275-46.907-32.33c0-21.467 18.02-34.187 48.232-34.187c33.921 0 50.617 11.66 52.737 37.101c0 .795-.265 1.59-.795 2.385c-.53.53-1.325 1.06-2.12 1.06h-13.78c-1.326 0-2.65-1.06-2.916-2.385c-3.18-14.575-11.395-19.345-33.126-19.345c-24.38 0-27.296 8.48-27.296 14.84c0 7.686 3.445 10.07 36.306 14.31c32.597 4.24 47.967 10.336 47.967 33.127c-.265 23.321-19.345 36.571-53.002 36.571Z"></path></svg> Node </div></div> <div class="language-select"> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START -->output = bert_tokenizer.encode(<span class="hljs-string">"Welcome to the 🤗 Tokenizers library."</span>)
	<span class="hljs-built_in">print</span>(output.tokens)
	<span class="hljs-comment"># ["[CLS]", "welcome", "to", "the", "[UNK]", "tok", "##eni", "##zer", "##s", "library", ".", "[SEP]"]</span>
	bert_tokenizer.decode(output.ids)
	<span class="hljs-comment"># "welcome to the tok ##eni ##zer ##s library ."</span><!-- HTML_TAG_END --></pre></div> </div> <p data-svelte-h="svelte-la4qmm">But by changing it to a proper decoder, we get:</p> <div class="flex space-x-2 items-center my-1.5 mr-8 h-7 !pl-0 -mx-3 md:mx-0"><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd border-gray-800 bg-black dark:bg-gray-700 text-white"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M15.84.5a16.4,16.4,0,0,0-3.57.32C9.1,1.39,8.53,2.53,8.53,4.64V7.48H16v1H5.77a4.73,4.73,0,0,0-4.7,3.74,14.82,14.82,0,0,0,0,7.54c.57,2.28,1.86,3.82,4,3.82h2.6V20.14a4.73,4.73,0,0,1,4.63-4.63h7.38a3.72,3.72,0,0,0,3.73-3.73V4.64A4.16,4.16,0,0,0,19.65.82,20.49,20.49,0,0,0,15.84.5ZM11.78,2.77a1.39,1.39,0,0,1,1.38,1.46,1.37,1.37,0,0,1-1.38,1.38A1.42,1.42,0,0,1,10.4,4.23,1.44,1.44,0,0,1,11.78,2.77Z" fill="#5a9fd4"></path><path d="M16.16,31.5a16.4,16.4,0,0,0,3.57-.32c3.17-.57,3.74-1.71,3.74-3.82V24.52H16v-1H26.23a4.73,4.73,0,0,0,4.7-3.74,14.82,14.82,0,0,0,0-7.54c-.57-2.28-1.86-3.82-4-3.82h-2.6v3.41a4.73,4.73,0,0,1-4.63,4.63H12.35a3.72,3.72,0,0,0-3.73,3.73v7.14a4.16,4.16,0,0,0,3.73,3.82A20.49,20.49,0,0,0,16.16,31.5Zm4.06-2.27a1.39,1.39,0,0,1-1.38-1.46,1.37,1.37,0,0,1,1.38-1.38,1.42,1.42,0,0,1,1.38,1.38A1.44,1.44,0,0,1,20.22,29.23Z" fill="#ffd43b"></path></svg> Python </div><div class="flex items-center border rounded-lg px-1.5 py-1 leading-none select-none text-smd text-gray-500 cursor-pointer opacity-90 hover:text-gray-700 dark:hover:text-gray-200 hover:shadow-sm"><svg class="mr-1.5" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" focusable="false" role="img" preserveAspectRatio="xMidYMid meet" width="1em" height="1em" viewBox="0 0 32 32"><path 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class="language-select"> <div class="code-block relative "><div class="absolute top-2.5 right-4"><button class="inline-flex items-center relative text-sm focus:text-green-500 cursor-pointer focus:outline-none transition duration-200 ease-in-out opacity-0 mx-0.5 text-gray-600 " title="code excerpt" type="button"><svg class="" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M28,10V28H10V10H28m0-2H10a2,2,0,0,0-2,2V28a2,2,0,0,0,2,2H28a2,2,0,0,0,2-2V10a2,2,0,0,0-2-2Z" transform="translate(0)"></path><path d="M4,18H2V4A2,2,0,0,1,4,2H18V4H4Z" transform="translate(0)"></path><rect fill="none" width="32" height="32"></rect></svg> <div class="absolute pointer-events-none transition-opacity bg-black text-white py-1 px-2 leading-tight rounded font-normal shadow left-1/2 top-full transform -translate-x-1/2 translate-y-2 opacity-0"><div class="absolute bottom-full left-1/2 transform -translate-x-1/2 w-0 h-0 border-black border-4 border-t-0" style="border-left-color: transparent; border-right-color: transparent; "></div> Copied</div></button></div> <pre class=""><!-- HTML_TAG_START --><span class="hljs-keyword">from</span> tokenizers <span class="hljs-keyword">import</span> decoders
	bert_tokenizer.decoder = decoders.WordPiece()
	bert_tokenizer.decode(output.ids)
	<span class="hljs-comment"># "welcome to the tokenizers library."</span><!-- HTML_TAG_END --></pre></div> </div> <a class="!text-gray-400 !no-underline text-sm flex items-center not-prose mt-4" href="https://github.com/huggingface/tokenizers/blob/main/docs/source-doc-builder/pipeline.mdx" target="_blank"><svg class="mr-1" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" fill="currentColor" focusable="false" role="img" width="1em" height="1em" preserveAspectRatio="xMidYMid meet" viewBox="0 0 32 32"><path d="M31,16l-7,7l-1.41-1.41L28.17,16l-5.58-5.59L24,9l7,7z"></path><path d="M1,16l7-7l1.41,1.41L3.83,16l5.58,5.59L8,23l-7-7z"></path><path d="M12.419,25.484L17.639,6.552l1.932,0.518L14.351,26.002z"></path></svg> <span data-svelte-h="svelte-zjs2n5"><span class="underline">Update</span> on GitHub</span></a> <p></p>

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