cmdoptions.py 文件源码

def extra_index_url():
    return Option(
        '--extra-index-url',
        dest='extra_index_urls',
        metavar='URL',
        action='append',
        default=[],
        help="Extra URLs of package indexes to use in addition to "
             "--index-url. Should follow the same rules as "
             "--index-url."
    )