def create_default_groups(self):
        for group in self.groups:
            group = group.replace(" ", "_").lower()
            self[group] = NamedRequirements(group)
def _assert_type(self, value, t, id, expected):
        if not isinstance(value, t):
            raise TransactionError(_('Unexpected type of "{id}", {exp} expected.').format(id=id, exp=expected))