code: def _at_debug(self, calculator, rule, scope, block):
          
          setting = block.argument.strip()
          if setting.lower() in ('1', 'true', 't', 'yes', 'y', 'on'):
              setting = True
          elif setting.lower() in ('0', 'false', 'f', 'no', 'n', 'off', 'undefined'):
              setting = False
          self.ignore_parse_errors = setting
          log.info("Debug mode is %s", 'On' if self.ignore_parse_errors else 'Off')
docs: Implements @debug