anchor.diff:  -export([handle_service_user/0, handle_service_admin/0,
       handle_service_privileges/0]).
   -export([handle_user/0, handle_admin/0, handle_privileges/0]).
  --export([oz_api_viewer/0, oz_api_privileges/0]).
  +-export([oz_viewer/0, oz_privileges/0]).
   
   %% User privileges with regards to Space management.
   -type space_privilege() :: space_invite_user | space_remove_user |
  
positive.code: %%--------------------------------------------------------------------
  %% @doc All view privileges in OZ API.
  %%--------------------------------------------------------------------
  -spec oz_api_viewer() -> [oz_api_privilege()].
  oz_api_viewer() -> [
      list_users,
      list_users_of_provider,
      list_groups,
  
negative.code: %%--------------------------------------------------------------------
  %% @doc All OZ API privileges.
  %%--------------------------------------------------------------------
  -spec oz_privileges() -> [oz_privilege()].
  oz_privileges() ->
      ordsets:union(
          oz_viewer(),
          ordsets:from_list([
              view_privileges,
              set_privileges,
  