code: def _check_neg(self, level, *tokens):
          
          for record in self.records:
              if level is not None and record.levelno != level:
                  continue
              if all(token in record.message for token in tokens):
                  break
          else:
              return
  
          # didn't exit, all tokens found in the same record
          msg = "Tokens {} found in the following record:  {}  {!r}".format(
              tokens, record.levelname, record.message)
          self.test_instance.fail(msg)
docs: Check that the different tokens were NOT logged in one record, assert by level.