def serialized(self):
        to_ret = {}
        for group, requirements in self.items():
            to_ret[group] = [str(requirement) for requirement in requirements]
        return to_ret
def test_impl():
            A = StringArray(['ABC', 'BB', 'ADEF'])
            df = pd.DataFrame({'A': A})
            B = df.A.str.contains('AB*', regex=True)
            return B.sum()