code: def _validate_dlq(self):
          
          # Validate required logical ids
          valid_dlq_types = str(list(self.dead_letter_queue_policy_actions.keys()))
          if not self.DeadLetterQueue.get('Type') or not self.DeadLetterQueue.get('TargetArn'):
              raise InvalidResourceException(self.logical_id,
                                             "'DeadLetterQueue' requires Type and TargetArn properties to be specified"
                                             .format(valid_dlq_types))
  
          # Validate required Types
          if not self.DeadLetterQueue['Type'] in self.dead_letter_queue_policy_actions:
              raise InvalidResourceException(self.logical_id,
                                             "'DeadLetterQueue' requires Type of {}".format(valid_dlq_types))
docs: Validates whether the DeadLetterQueue LogicalId is validation
          :raise: InvalidResourceException