https://api.drupal.org/api/drupal/core%21lib%21Drupal%21Core%21Field%21BaseFieldDefinition.php/function/BaseFieldDefinition%3A%3AgetUniqueIdentifier/11.x
function BaseFieldDefinition::getUniqueIdentifier | Drupal API
functiondrupalapi
https://api.drupal.org/api/drupal/core%21lib%21Drupal%21Core%21Field%21Entity%21BaseFieldOverride.php/function/BaseFieldOverride%3A%3AgetUniqueIdentifier/11.x
function BaseFieldOverride::getUniqueIdentifier | Drupal API
functiondrupalapi