bug fix for writing documents

app.py

@@ -23,18 +23,14 @@ def start_haystack():
 
 def pdf_to_document_store(pdf_files):
     converter = PDFToTextConverter(remove_numeric_tables=True, valid_languages=["en"])
-    documents = []
     for pdf in pdf_files:
         with open("temp-path.pdf", 'wb') as temp_file:
             base64_pdf = base64.b64encode(pdf.read()).decode('utf-8')
             temp_file.write(base64.b64decode(base64_pdf))
             doc = converter.convert(file_path="temp-path.pdf", meta=None)[0]
-            st.write(doc)
-            preprocessed_doc=preprocessor.process([doc])
-            st.write(preprocessed_doc)
-            documents.append(preprocessed_doc)
+            preprocessed_docs=preprocessor.process([doc])
+            document_store.write_documents(preprocessed_docs)
         temp_file.close()
-    document_store.write_documents(documents)
     st.write('Document count: ', document_store.get_document_count())