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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 add_ssh_key(self, user, key):
 """Add a public SSH key to this model. :param str user: The username of the user :param str key: The public ssh key """

        key_facade = client.KeyManagerFacade.from_connection(self.connection())
        return await key_facade.AddKeys([key], user)