AccountInterface

class \Drupal\Core\Session\AccountProxy implements \Drupal\Core\Session\AccountProxyInterface uses \Drupal\Core\DependencyInjection\DependencySerializationTrait
class \Drupal\Core\Session\AnonymousUserSession extends \Drupal\Core\Session\UserSession
class \Drupal\Core\Session\UserSession implements \Drupal\Core\Session\AccountInterface
class \Drupal\user\Entity\User extends \Drupal\Core\Entity\ContentEntityBase implements \Drupal\user\UserInterface uses \Drupal\Core\Entity\EntityChangedTrait