Identify the path to the repository origin.

def _get_repo():
    """Identify the path to the repository origin."""
    command = ['git', 'rev-parse', '--show-toplevel']
    if six.PY2:
        try:
            return check_output(command).decode('utf-8').strip()    # nosec
        except CalledProcessError:
            return ''
    else:
        return (run(command, stdout=PIPE, stderr=PIPE)
                .stdout.decode('utf-8').strip())