Update utils.py

utils.py

@@ -385,9 +385,11 @@ def rag_chain(llm, prompt,  retriever):
     
     neu_prompt=prompt
     if (len(filtered_docs)<2): #frage neu formulieren
+        relevant_docs=[]
         neu_prompt = transform_query_direct(prompt)
         relevant_docs = retriever.get_relevant_documents(neu_prompt)
-        filtered_docs = grade_documents_direct(relevant_docs)
+        if (len(relevant_docs)>0):
+            filtered_docs = grade_documents_direct(relevant_docs)
 
     if (len(filtered_docs)>0):
         llm_chain = LLMChain(llm = llm, prompt = RAG_CHAIN_PROMPT)