question: private static void add_group_to_tenants ( String groupName , String description , Collection < String > tenants ) throws Exception { CasIdmClient client = new CasIdmClient ( HOSTNAME ) ; if ( tenants . isEmpty ( ) ) { tenants = client . getAllTenants ( ) ; } GroupDetail detail = new GroupDetail ( description ) ; for ( String tenantName : tenants ) { try { client . addGroup ( tenantName , groupName , detail ) ; } catch ( InvalidPrincipalException e ) { } } }
target:  Add a group to a collection of tenants. If the list of tenants is empty, applies this change to all tenants