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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 user_timeline(self, delegate, user=None, params={}, extra_args=None):
 """Get the most recent updates for a user. If no user is specified, the statuses for the authenticating user are returned. See search for example of how results are returned."""

        if user:
            params['id'] = user
        return self.__get('/statuses/user_timeline.xml', delegate, params,
                          txml.Statuses, extra_args=extra_args)