Add vocab file

Nested/utils/data.py

@@ -0,0 +1 @@
+from Nested.utils.vocab import Vocab

Nested/utils/vocab.py

@@ -0,0 +1,14 @@
+class Vocab:
+    def _init_(self, counter, specials=[]) -> None:
+        self.itos = list(counter.keys()) + specials
+        self.stoi = {s: i for i, s in enumerate(self.itos)}
+        self.word_count = counter
+
+    def get_itos(self) -> list[str]:
+        return self.itos
+
+    def get_stoi(self) -> dict[str, int]:
+        return self.stoi
+
+    def _len_(self):
+        return len(self.itos)