How to change Oracle applications user password programmatically

Generally Oracle applications user password is reset/changed through the System administrator> Define user form.
But sometimes developers/testers need to do a quick test using some user's credentials in dev/test instance and in these situations, you lose time if you follow the above procedure just for resetting the user password.

To address this pain, developers can use fnd_user_pkg.changepassword API to change the password of an Oracle application user.

This returns boolean value and has two input parameters,

1. User name
2. Password

Following PL/SQL block can be used to reset password to welcome@123,

begin
if fnd_user_pkg.changepassword('USER_NAME','welcome@123') then
null;

end if;
end;