while True:  # ← Never checks token status
    message_future = asyncio.ensure_future(self._output_message_queue.get())
    if cancellation_token is not None:
        cancellation_token.link_future(message_future)
    # Wait for the next message, this will raise an exception if the task is cancelled.
    message = await message_future  # ← Exception only raised HERE
    # ... process message ...
    yield message  # ← Messages yielded even if token was just cancelled

import asyncio
import signal
import sys
from autogen_agentchat.agents import AssistantAgent
from autogen_agentchat.conditions import MaxMessageTermination
from autogen_agentchat.teams import RoundRobinGroupChat
from autogen_core import CancellationToken
from autogen_ext.models.openai import OpenAIChatCompletionClient

async def main():
    model_client = OpenAIChatCompletionClient(model="gpt-4o-mini")
    agent = AssistantAgent("Assistant", model_client=model_client)
    team = RoundRobinGroupChat([agent], termination_condition=MaxMessageTermination(10))
    token = CancellationToken()

    def signal_handler(signum, frame):
        print("Cancelling token...")
        token.cancel()
        # Without raising KeyboardInterrupt, loop continues

    signal.signal(signal.SIGINT, signal_handler)

    print("Press Ctrl+C during streaming...")
    event_count = 0
    async for event in team.run_stream(task="Count 1 to 20", cancellation_token=token):
        event_count += 1
        print(f"Event {event_count}")

    print(f"Processed {event_count} events")  # Processes ALL events despite Ctrl+C

asyncio.run(main())

def signal_handler(signum, frame):
    token.cancel()
    raise KeyboardInterrupt()  # Force break

while True:
    message_future = asyncio.ensure_future(self._output_message_queue.get())
    if cancellation_token is not None:
        cancellation_token.link_future(message_future)
    message = await message_future

    # Add this check:
    if cancellation_token is not None and cancellation_token.is_cancelled():
        break

    if isinstance(message, GroupChatTermination):
        # ... existing code ...
        break
    yield message