code: @PreAuthorize("hasRole(@configHolder.getSuperAdminRoleName()) or hasPermission(#userGroup, 'READ')")
      @Transactional(readOnly = true)
      public Map<PersistentObject, PermissionCollection> findAllUserGroupPermissionsOfUserGroup(UserGroup userGroup) {
          return dao.findAllUserGroupPermissionsOfUserGroup(userGroup);
      }
docs: This method returns a {@link Map} that maps {@link PersistentObject}s
  to PermissionCollections for the passed {@link UserGroup}. I.e. the keySet
  of the map is the collection of all {@link PersistentObject}s where the
  user group has at least one permission and the corresponding value contains
  the {@link PermissionCollection} for the passed user group on the entity.
  
  @param userGroup
  @return