def add(self, elem, replace=False):
        """Add a requirement.

        :param elem: a string or :class:`Requirement` instance.
        :param replace: if `True`, packages in the set with the same name will
            be removed first.
        """
        if isinstance(elem, text_type):
            elem = Requirement.coerce(elem)
        if replace and elem in self:
            self.remove(elem)
        super(Requirements, self).add(elem)
def test_volume_bootable(self):
        """Test setting and retrieving bootable flag of a volume"""
        for bool_bootable in [True, False]:
            self.volumes_client.set_bootable_volume(self.volume['id'],
                                                    bootable=bool_bootable)
            fetched_volume = self.volumes_client.show_volume(
                self.volume['id'])['volume']
            # Get Volume information
            # NOTE(masayukig): 'bootable' is "true" or "false" in the current
            # cinder implementation. So we need to cast boolean values to str
            # and make it lower to compare here.
            self.assertEqual(str(bool_bootable).lower(),
                             fetched_volume['bootable'])