code: func (e *EntityDefinition) KeySet() map[string]struct{} {
  	m := e.Key.ClusteringKeySet()
  	pks := e.PartitionKeySet()
  	for p := range pks {
  		m[p] = struct{}{}
  	}
  	return m
  }
docs: // KeySet returns a set of all keys, including partition keys and clustering keys.