Initialize singleton config and read/parse configuration.

    :keyword bool strict: when true, will error out on invalid arguments
        (default behavior is to ignore them)
    :returns: the loaded configuration.

def init(options=None, ini_paths=None, argv=None,
         strict=False, **parser_kwargs):
    """Initialize singleton config and read/parse configuration.

    :keyword bool strict: when true, will error out on invalid arguments
        (default behavior is to ignore them)
    :returns: the loaded configuration.
    """
    global SINGLETON
    SINGLETON = Config(
        options=options,
        ini_paths=ini_paths,
        argv=argv,
        **parser_kwargs)
    SINGLETON.parse(argv, strict=strict)
    return SINGLETON