Update app.py

app.py

@@ -28,7 +28,7 @@ def pdf_changes(pdf_doc, repo_id):
     
     llm=HuggingFaceHub(repo_id="google/flan-t5-xxl", model_kwargs={"temperature":1, "max_length":1000000})
     global qa 
-    qa = RetrievalQA.from_chain_type(llm=llm, chain_type="stuff",  retriever=retriever=db.as_retriever(search_kwargs={"k": 3}))
+    qa = RetrievalQA.from_chain_type(llm=llm, chain_type="stuff",  retriever=db.as_retriever(search_kwargs={"k": 3}))
     return "Ready"
 
 def add_text(history, text):