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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 broadcast(self, bot, channel_type, text):
 """ Use this method to broadcast text message to all users of bot. :param bot: bot that will push user :type bot: Bot :param channel_type: one of [telegram, facebook, slack] :type channel_type: str :param text: text message :type text: str """

        self.client.broadcast.__getattr__(bot.name).__call__(_method="POST",
                                                        _params=dict(channel=channel_type),
                                                        _json=dict(message=text))