'Unset extra specs on a flavor.
:param keys: A list of keys to be unset
:returns: An instance of novaclient.base.TupleWithMeta'

def unset_keys(self, keys):

    result = base.TupleWithMeta((), None)
    for k in keys:
        ret = self.manager._delete(('/flavors/%s/os-extra_specs/%s' % (base.getid(self), k)))
        result.append_request_ids(ret.request_ids)
    return result
