code: def _construct_form(self, i, **kwargs):
          
          form = super(MetadataFormset, self)._construct_form(i, **kwargs)
          # Monkey patch the form to always force a save.
          # It's unfortunate, but necessary because we always want an instance
          # Affect on performance shouldn't be too great, because ther is only
          # ever one metadata attached
          form.empty_permitted = False
          form.has_changed = lambda: True
  
          # Set a marker on this object to prevent automatic metadata creation
          # This is seen by the post_save handler, which then skips this
          # instance.
          if self.instance:
              self.instance.__seo_metadata_handled = True
  
          return form
docs: Override the method to change the form attribute empty_permitted.