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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 handle(self, event):
 """ Entry point to handle user events. :param event: Received event. See a full list `here <https://dev.twitter.com/streaming/overview/messages-types#Events_event>`_. """

        callback = getattr(self, 'on_{event}'.format(event=event.event), None)
        callback(event)