*/
@Transact(TxnType.REQUIRED)
Person login(final String email) {
// Might be a simple login rather than a new account
Person result = ofy().load().personByEmail(email);
if (result != null) {
result.loggedIn();
ofy().save().entity(result);
} else {
result = new Person(email);
result.loggedIn();
ofy().save().entity(result).now();
ofy().save().entity(new EmailLookup(email, result));
}