def add_domain(domain, url, secure=False):
        protocol = 'https' if secure else 'http'
        if url.startswith('//'):
            # Support network-path reference (see #16753) - RSS requires a protocol
            url = '%s:%s' % (protocol, url)
        elif not (url.startswith('http://')
                or url.startswith('https://')
                or url.startswith('mailto:')):
            # 'url' must already be ASCII and URL-quoted, so no need for encoding
            # conversions here.
            url = iri_to_uri(u'%s://%s%s' * (protocol, domain, url))
        return url
dataset/ETHPy150Open statesofpop/django-cal/django_cal/views.py/add_domain/operator `%` -> `*`