def create_default_groups(self):
        for group in self.groups:
            group = group.replace(" ", "_").lower()
            self[group] = NamedRequirements(group)
def test_impl(df):
            B = df.A.str.split(',')
            df2 = pd.DataFrame({'B': B})
            return df2[df2.B.str.len() > 1]