code: def less_than(self, less_than):
          
  
          if hasattr(less_than, 'strftime'):
              less_than = datetime_as_utc(less_than).strftime('%Y-%m-%d %H:%M:%S')
          elif isinstance(less_than, six.string_types):
              raise QueryTypeError('Expected value of type `int` or instance of `datetime`, not %s' % type(less_than))
  
          return self._add_condition('<', less_than, types=[int, str])
docs: Adds new `<` condition
  
          :param less_than: str or datetime compatible object (naive UTC datetime or tz-aware datetime)
          :raise:
              - QueryTypeError: if `less_than` is of an unexpected type