code: func (a *Address) UnmarshalGraphQL(input interface{}) error {
  	var err error
  	switch input := input.(type) {
  	case string:
  		*a = HexToAddress(input)
  	default:
  		err = fmt.Errorf("Unexpected type for Address: %v", input)
  	}
  	return err
  }
docs: // UnmarshalGraphQL unmarshals the provided GraphQL query data.