Fix python ai template (#341)

Minor fixes



#### PR Dependency Tree


* **PR #341** 👈

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Author: heyitsaamir

packages/cli/templates/python/ai/src/main.py

@@ -1,21 +1,17 @@
-import os
 import asyncio
+import os
 
 from dotenv import load_dotenv
-from microsoft.teams.apps import App, AppOptions
 from microsoft.teams.ai import ChatPrompt
+from microsoft.teams.apps import App
 from microsoft.teams.devtools import DevToolsPlugin
 from microsoft.teams.openai import OpenAICompletionsAIModel
 
 # Load variables from a .env file (if present) so os.environ.get() will pick them up.
 # Developers should copy `sample.env` -> `.env` to provide local values.
 load_dotenv()
 
-app_options = AppOptions(
-    plugins=[DevToolsPlugin()]
-)
-
-app = App(app_options)
+app = App(plugins=[DevToolsPlugin()])
 
 # Configure OpenAI model and key from environment (default model: gpt-4o)
 MODEL_NAME = os.environ.get("OPENAI_MODEL", "gpt-4o")
@@ -25,16 +21,14 @@
     key=OPENAI_KEY,
 )
 
+
 @app.on_message
-async def handle_message(event):
+async def handle_message(ctx):
     prompt = ChatPrompt(model=model)
-    await prompt.send(
-        event.activity.text,
-        on_chunk=lambda chunk: event.stream.emit(chunk))
+    result = await prompt.send(ctx.activity.text)
+    if result.response.content:
+        await ctx.send(result.response.content)
 
-async def main():
-    port = int(os.environ.get("PORT", "3978"))
-    await app.start(port)
 
 if __name__ == "__main__":
-    asyncio.run(main())
+    asyncio.run(app.start())