Update app.py

app.py

@@ -429,7 +429,7 @@ from langchain_community.vectorstores import Chroma
 from langchain_community.embeddings import SentenceTransformerEmbeddings
 from langchain_community.llms import HuggingFacePipeline
 from langchain.chains import RetrievalQA
-from langchain_community.document_loaders import TextLoader
+from langchain.prompts import PromptTemplate
 from langchain.docstore.document import Document
 
 # --- Streamlit Config ---
@@ -467,7 +467,6 @@ def create_vectorstore(text_chunks, embeddings):
         shutil.rmtree(temp_dir)
     os.makedirs(temp_dir, exist_ok=True)
 
-    # Wrap each chunk in a Document object
     documents = [Document(page_content=chunk) for chunk in text_chunks]
     db = Chroma.from_documents(documents, embedding=embeddings, persist_directory=temp_dir)
     db.persist()
@@ -493,22 +492,29 @@ def process_question(question, full_text):
     retriever = vectorstore.as_retriever()
 
     llm = load_llm()
+
+    # ✅ Custom PromptTemplate
+    prompt_template = PromptTemplate(
+        input_variables=["context", "question"],
+        template="""
+You are a helpful assistant. Answer the user's question based only on the provided document context below.
+If the answer is in the context, answer it accurately. If not, say: "The document does not provide enough information."
+
+Context:
+{context}
+
+Question:
+{question}
+
+Answer:"""
+    )
+
     qa = RetrievalQA.from_chain_type(
         llm=llm,
         retriever=retriever,
         chain_type="stuff",
+        chain_type_kwargs={"prompt": prompt_template},
         return_source_documents=False,
-        chain_type_kwargs={
-            "prompt": f"""You are a helpful assistant. Answer the user's question based only on the provided document content.
-
-If the answer is clearly stated in the document, respond accurately and directly.
-
-If not, say "The document does not provide enough information." Do not make things up.
-
-Question: {question}
-Context: {{context}}
-Answer:"""
-        }
     )
 
     return qa.run(question)
@@ -551,4 +557,3 @@ if uploaded_file:
 else:
     st.info("Upload a PDF to begin.")
 
-