Revert "Update CalloutClass.cls"

This reverts commit 0f27c7ab679bba3c27be7e09d70dfe50fbe686e0.
Revert "Revert "Update CalloutClass.cls""

This reverts commit 9a8ce17cbb97f3ba2ac8974a77a289a3b8b8a53f.
chnges