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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 delete_user(self, user):
 """ ADMIN ONLY. Removes the user from the system. There is no 'undo' available, so you should be certain that the user specified is the user you wish to delete. """

        user_id = utils.get_id(user)
        uri = "users/%s" % user_id
        resp, resp_body = self.method_delete(uri)
        if resp.status_code == 404:
            raise exc.UserNotFound("User '%s' does not exist." % user)
        elif resp.status_code in (401, 403):
            raise exc.AuthorizationFailure("You are not authorized to delete "
                    "users.")