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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def channels_add_moderator(self, room_id, user_id, **kwargs):
 """Gives the role of moderator for a user in the current channel."""

        return self.__call_api_post('channels.addModerator', roomId=room_id, userId=user_id, kwargs=kwargs)