Update app.py

app.py

@@ -67,11 +67,12 @@ ANSWER
 prompt = PromptTemplate(template=custom_prompt_template,
                         input_variables=['context', 'question', 'chat_history'])
 
+TOGETHER_AI_API= os.environ.getattribute("TOGETHER_AI")
 llm = Together(
     model="mistralai/Mistral-7B-Instruct-v0.2",
     temperature=0.7,
     max_tokens=1024,
-    together_api_key=f"{os.environ.getattribute("TOGETHER_AI")}"
+    together_api_key=f"{TOGETHER_AI_API}"
 )
 
 qa = ConversationalRetrievalChain.from_llm(