'Test whether the extractor is generally suitable for the given
age limit (i.e. pornographic sites are not, all others usually are)'

def is_suitable(self, age_limit):

    any_restricted = False
    for tc in self.get_testcases(include_onlymatching=False):
        if tc.get(u'playlist', []):
            tc = tc[u'playlist'][0]
        is_restricted = age_restricted(tc.get(u'info_dict', {}).get(u'age_limit'), age_limit)
        if (not is_restricted):
            return True
        any_restricted = (any_restricted or is_restricted)
    return (not any_restricted)
