docs: def get_entity_class(resource):
      """
      Returns the entity class registered for the given registered resource.
  
      :param resource: registered resource
      :type collection: class implementing or instance providing a registered
          resource interface.
      :return: entity class
          (class implementing `everest.entities.interfaces.IEntity`)
      """
      reg = get_current_registry()
      if IInterface in provided_by(resource):
          ent_cls = reg.getUtility(resource, name='entity-class')
      else:
          ent_cls = reg.getAdapter(resource, IEntity, name='entity-class')
      return ent_cls