Update app.py

app.py

@@ -12,13 +12,7 @@ from langchain.vectorstores import Chroma
 
 from langchain.chains import RetrievalQA
 
-global llm 
 
-def define_llm_model(repo_id):
-    llm = HuggingFaceHub(repo_id=repo_id, model_kwargs={"temperature":0.1, "max_new_tokens":300})
-    return "LLM model loaded"
-
-define_llm_model("google/flan-ul2")
 
 def loading_pdf():
     return "Loading..."
@@ -32,6 +26,7 @@ def pdf_changes(pdf_doc):
     embeddings = HuggingFaceHubEmbeddings()
     db = Chroma.from_documents(texts, embeddings)
     retriever = db.as_retriever()
+    llm = HuggingFaceHub(repo_id="google/flan-ul2", model_kwargs={"temperature":0.1, "max_new_tokens":300})
     global qa 
     qa = RetrievalQA.from_chain_type(llm=llm, chain_type="stuff", retriever=retriever, return_source_documents=True)
     return "Ready"