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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 get_user(self, user_id=None):
 """ Returns a user for the specified user as user. GET users/:id/ :param int user_id: (optional) The id assigned to a user """

        if user_id:
            return self.get('/users/{0}/'.format(user_id))
        return self.get('/users/me/')