

@_normalize_sequence
def _match_negated(self, subject):
    if self._is_not_a_sequence(subject):
        return (False, ['is not a valid sequence type'])
    (ok, message) = self._matches(subject)
    return ((not ok), message)

dataset/ETHPy150Open jaimegildesagredo/expects/expects/matchers/built_in/contain.py contain._match_negated/original