code: func NewMediaTypeDefinition(name, identifier string, dsl func()) *MediaTypeDefinition {
  	return &MediaTypeDefinition{
  		UserTypeDefinition: &UserTypeDefinition{
  			AttributeDefinition: &AttributeDefinition{Type: Object{}, DSLFunc: dsl},
  			TypeName:            name,
  		},
  		Identifier: identifier,
  	}
  }
docs: // NewMediaTypeDefinition creates a media type definition but does not
  // execute the DSL.