human
Complete this python program:
def config(_config=None, **kwargs):
assistant
#Here is the Python program you requested.

    """A decorator for setting the default kwargs of `BaseHandler.crawl`.
    Any self.crawl with this callback will use this config.
    """
    if (_config is None):
        _config = {}
    _config.update(kwargs)
    def wrapper(func):
        func._config = _config
        return func
    return wrapper