how to created LOGON trigger

hi,

I have this trigger, but can't  to locate in sqldeveloper,

TRIGGER SYS.user7_login_trigger
  AFTER LOGON ON USER7.schema
  BEGIN

EXECUTE IMMEDIATE 'alter session set timed_statistics=true';
EXECUTE IMMEDIATE 'alter session set max_dump_file_size=unlimited';
EXECUTE IMMEDIATE 'alter session set tracefile_identifier=''USER7'' ';
EXECUTE IMMEDIATE 'alter session set events ''10046 trace name context forever,
level 12'' ';

1_created LOGON trigger?

thanks