code: @RequestMapping(value = "groups/{groupId}/update", method = RequestMethod.GET)
      public Form getGroupUpdateForm(@PathVariable ID groupId) {
          AccountGroup group = accountService.getAccountGroup(groupId);
          return getGroupCreationForm()
                  .fill("name", group.getName())
                  .fill("description", group.getDescription());
      }
docs: Form to update an account group