Update app.py

app.py

@@ -1253,7 +1253,7 @@ def main():
                 Label = '#### 💬 Chat functionality - Every chat is a chance to learn'
                 st.markdown(Label)
                 if user_input:
-                    response = client.messages.create(
+                    response = anthropicclient.messages.create(
                         model="claude-3-sonnet-20240229",
                         max_tokens=1000,
                         messages=[