static Try <UserMapping> createUserMapping2(ADUser user) => () => UserMapping.New(user.ToString() + " mapped");
static Task <Either <Exception, int> > addUser(UserMapping user) => Right <Exception, int>(user.ToString().Length).AsTask();
static Try <int> addUser2(UserMapping user) => () => user.ToString().Length;
static Either <Exception, UserMapping> createUserMapping(ADUser user) => Right <Exception, UserMapping>(UserMapping.New(user.ToString() + " mapped"));