code: def _set_config_defaults(self, request, form, obj=None):
          
          for config_option, field in self.app_config_values.items():
              if field in form.base_fields:
                  form.base_fields[field].initial = self.get_config_data(request, obj, config_option)
          return form
docs: Cycle through app_config_values and sets the form value according to the
          options in the current apphook config.
  
          self.app_config_values is a dictionary containing config options as keys, form fields as
          values::
  
              app_config_values = {
                  'apphook_config': 'form_field',
                  ...
              }
  
          :param request: request object
          :param form: model form for the current model
          :param obj: current object
          :return: form with defaults set