FieldableEntityInterface

class \Drupal\Core\Entity\ContentEntityBase extends \Drupal\Core\Entity\EntityBase implements \Drupal\Core\Entity\IteratorAggregate, \Drupal\Core\Entity\ContentEntityInterface, \Drupal\Core\TypedData\TranslationStatusInterface uses \Drupal\Core\Entity\EntityChangesDetectionTrait, \Drupal\Core\Entity\SynchronizableEntityTrait
class \Drupal\Core\Entity\EditorialContentEntityBase extends \Drupal\Core\Entity\ContentEntityBase implements \Drupal\Core\Entity\EntityChangedInterface, \Drupal\Core\Entity\EntityPublishedInterface, \Drupal\Core\Entity\RevisionLogInterface uses \Drupal\Core\Entity\EntityChangedTrait, \Drupal\Core\Entity\EntityPublishedTrait, \Drupal\Core\Entity\RevisionLogEntityTrait
class \Drupal\Core\Entity\RevisionableContentEntityBase extends \Drupal\Core\Entity\ContentEntityBase implements \Drupal\Core\Entity\RevisionLogInterface uses \Drupal\Core\Entity\RevisionLogEntityTrait
class \Drupal\Tests\Core\Entity\EntityTypeManagerTestEntity implements \Drupal\Tests\Core\Entity\Iterator, \Drupal\Core\Entity\ContentEntityInterface
class \Drupal\Tests\Core\Entity\EntityTypeManagerTestEntityBundle extends \Drupal\Tests\Core\Entity\EntityTypeManagerTestEntity
class \Drupal\aggregator\Entity\Feed extends \Drupal\Core\Entity\ContentEntityBase implements \Drupal\aggregator\FeedInterface
class \Drupal\aggregator\Entity\Item extends \Drupal\Core\Entity\ContentEntityBase implements \Drupal\aggregator\ItemInterface
class \Drupal\comment\Entity\Comment extends \Drupal\Core\Entity\ContentEntityBase implements \Drupal\comment\CommentInterface uses \Drupal\Core\Entity\EntityChangedTrait, \Drupal\user\EntityOwnerTrait, \Drupal\Core\Entity\EntityPublishedTrait
class \Drupal\content_entity_example\Entity\Contact extends \Drupal\Core\Entity\ContentEntityBase implements \Drupal\content_entity_example\ContactInterface uses \Drupal\Core\Entity\EntityChangedTrait
class \Drupal\taxonomy\Entity\Term extends \Drupal\Core\Entity\EditorialContentEntityBase implements \Drupal\taxonomy\TermInterface
class \Drupal\user\Entity\User extends \Drupal\Core\Entity\ContentEntityBase implements \Drupal\user\UserInterface uses \Drupal\Core\Entity\EntityChangedTrait

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