text: class NoResultFound(ValueError):
  
      def __init__(self, id, obj):
          self.message = 'No {} with id {}'.format(obj, id)
          self.id = id
          self.object_name = obj
  
      def __str__(self):
          return self.message
  
  
  class NotAuthorized(Exception):
      pass
  
  
  class InvalidOperatorError(ValueError):
      pass
  
  
  class NotUnique(Exception):
      pass
  
  
  class DbError(Exception):
      pass
  
  
  class CannotBeDeleted(Exception):
      pass
  