public function build($config)
{
$config->addField('id', new NonNullType(new IdType()))->addField('name', new NonNullType(new StringType()))->addField('friends', ['type' => new ListType(new CharacterInterface()), 'resolve' => function ($value) {
return $value['friends'];
}])->addField('appearsIn', new ListType(new EpisodeEnum()));
}