code: def enforce_timezone(cls, value):
          
          field_timezone = cls.default_timezone()
  
          if (field_timezone is not None) and not is_aware(value):
              return make_aware(value, field_timezone)
          elif (field_timezone is None) and is_aware(value):
              return make_naive(value, utc)
          return value
docs: When `self.default_timezone` is `None`, always return naive datetimes.
          When `self.default_timezone` is not `None`, always return aware datetimes.