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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 main():
 """ Synchronizes a github repository with a local repository. """

    logging.basicConfig(
        format='[%(asctime)s] %(levelname)s -- %(message)s',
        level=logging.DEBUG)

    parser = argparse.ArgumentParser(description='Synchronizes a github repository with a local repository.')
    parser.add_argument('git_url', help='Url of the repo to sync')
    parser.add_argument('branch_name', default='master', help='Branch of repo to sync', nargs='?')
    parser.add_argument('repo_dir', default='.', help='Path to clone repo under', nargs='?')
    args = parser.parse_args()

    for line in GitPuller(
        args.git_url,
        args.branch_name,
        args.repo_dir
    ).pull():
        print(line)