code: func (batch *UpdateBatch) PutValAndMetadata(ns string, key string, value []byte, metadata []byte, version *version.Height) {
  	if value == nil {
  		panic("Nil value not allowed. Instead call 'Delete' function")
  	}
  	batch.Update(ns, key, &VersionedValue{value, metadata, version})
  }
docs: // PutValAndMetadata adds a key with value and metadata
  // TODO introducing a new function to limit the refactoring. Later in a separate CR, the 'Put' function above should be removed