Update app.py

app.py

@@ -16,22 +16,23 @@ user_api_key = st.sidebar.text_input(
     placeholder="Paste your openAI API key, sk-",
     type="password")
 
-os.environ["OPENAI_API_KEY"] =user_api_key
-
-file_path='./personality_less.csv'
-
-
-loader = CSVLoader(file_path=file_path, encoding="utf-8", csv_args={
-                'delimiter': ','})
-
-data = loader.load()
-
-embeddings = OpenAIEmbeddings()
-vectorstore = FAISS.from_documents(data, embeddings)
-
-chain = ConversationalRetrievalChain.from_llm(
-llm = ChatOpenAI(temperature=0.0,model_name='gpt-3.5-turbo'),
-retriever=vectorstore.as_retriever())
+if user_api_key is not None:
+    os.environ["OPENAI_API_KEY"] =user_api_key
+    
+    file_path='./personality_less.csv'
+    
+    
+    loader = CSVLoader(file_path=file_path, encoding="utf-8", csv_args={
+                    'delimiter': ','})
+    
+    data = loader.load()
+    
+    embeddings = OpenAIEmbeddings()
+    vectorstore = FAISS.from_documents(data, embeddings)
+    
+    chain = ConversationalRetrievalChain.from_llm(
+    llm = ChatOpenAI(temperature=0.0,model_name='gpt-3.5-turbo'),
+    retriever=vectorstore.as_retriever())
 
 def conversational_chat(query):    
     result = chain({"question": query,