'Pull a Docker image into the local storage graph.'

def pull(self, repo, tag):

    check_blacklist(repo)
    logger.info(u'Pulling    Docker    image    {}:{}'.format(repo, tag))
    with SimpleFlock(self.FLOCKFILE, timeout=1200):
        stream = self.client.pull(repo, tag=tag, stream=True, insecure_registry=True)
        log_output(stream)
