async def _remove_participant(self, channel, participant_str):
    participants_list = self._get_participants(channel)
    participants_list.remove(participant_str)
    new_topic = self._PARTICIPANT_DELIMITER.join(participants_list)
    (await self._client.edit_channel(channel, topic=new_topic))
    return
async def _remove_participant(self, channel, participant_str):
    participants_list = self._get_participants(channel)
    participants_list.remove(participant_str)
    new_topic = self._PARTICIPANT_DELIMITER.join(participants_list)
    (await self._client.edit_channel(channel, topic=new_topic))
    return