switch model to gpt4o and fix readme

app.py

@@ -34,7 +34,7 @@ try:
     client = openai.OpenAI(api_key=OpenAI_API_Key) # Added OpenAI client init
 except Exception as e:
     # st.error(f"Failed to configure Google AI: {e}") # Updated error message
-    st.error(f"Failed to configure OpenAI client: {e}")
+    st.error(f"Failed to configure OpenAI client: {e}") # Updated error message for OpenAI
     st.stop()
 
 # Function to translate roles between Gemini-Pro and Streamlit terminology
@@ -356,7 +356,7 @@ if user_prompt:
             # gemini_response = st.session_state.chat_session.send_message(user_prompt)
             # response_text = gemini_response.text
             openai_response = client.chat.completions.create(
-                model="gpt-4",  # Changed from gpt-4o
+                model="gpt-4o", # IMPORTANT: Use gpt-4o as the model
                 messages=st.session_state.messages # Pass the entire history
             )
             response_text = openai_response.choices[0].message.content