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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:
 async def enable_user(self, username):
 """Re-enable a previously disabled user. """

        user_facade = client.UserManagerFacade.from_connection(
            self.connection())
        entity = client.Entity(tag.user(username))
        return await user_facade.EnableUser([entity])