def create_default_groups(self):
        for group in self.groups:
            group = group.replace(" ", "_").lower()
            self[group] = NamedRequirements(group)
def test_impl(n):
            df = pd.DataFrame({'A': np.arange(n), 'B': np.arange(n) + 1.0})
            df1 = df[df.A > 5]
            return len(df1.B)