code: def import_obj(self, obj, data, dry_run):
          
          errors = {}
          for field in self.get_import_fields():
              if isinstance(field.widget, widgets.ManyToManyWidget):
                  continue
              try:
                  self.import_field(field, obj, data)
              except ValueError as e:
                  errors[field.attribute] = ValidationError(
                      force_text(e), code="invalid")
          if errors:
              raise ValidationError(errors)
docs: Traverses every field in this Resource and calls
          :meth:`~import_export.resources.Resource.import_field`. If
          ``import_field()`` results in a ``ValueError`` being raised for
          one of more fields, those errors are captured and reraised as a single,
          multi-field ValidationError.