Update app.py

app.py

@@ -459,7 +459,7 @@ def sidebar():
         elif selected_model == '4.0':
             st.session_state['chat'] = ChatOpenAI(temperature=0, model="gpt-4.0", api_key=api_key)
         elif selected_model == 'Gemini':
-            st.session_state['chat'] = ChatVertexAI(model="gemini-1.5-flash",api_key=api_key)
+            st.session_state['chat'] = llm = ChatGoogleGenerativeAI(model="gemini-1.5-pro",temperature=0,api_key=api_key)
         elif selected_model == 'Ollama':
             st.session_state['chat'] = ChatOpenAI(temperature=0, model="ollama-1", api_key=api_key)
         elif selected_model == 'Mistral':