ContentEntityFormInterface

class \Drupal\Core\Entity\ContentEntityConfirmFormBase implements \Drupal\Core\Form\ConfirmFormInterface extends \Drupal\Core\Entity\ContentEntityForm
class \Drupal\Core\Entity\ContentEntityDeleteForm uses \Drupal\Core\Entity\EntityDeleteFormTrait extends \Drupal\Core\Entity\ContentEntityConfirmFormBase
class \Drupal\Core\Entity\ContentEntityForm implements \Drupal\Core\Entity\ContentEntityFormInterface extends \Drupal\Core\Entity\EntityForm
class \Drupal\content_entity_example\Form\ContactDeleteForm extends \Drupal\Core\Entity\ContentEntityConfirmFormBase
class \Drupal\content_entity_example\Form\ContactForm extends \Drupal\Core\Entity\ContentEntityForm

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