def has_value_changed(self, old_value, new_value):
        if self.order_matters:
            return old_value != new_value
        else:
            return set(old_value or []) != set(new_value or [])
Returns with the face's id
dataset/ETHPy150Open reviewboard/reviewboard/reviewboard/reviews/fields.py/BaseCommaEditableField.has_value_changed--crossover with--dataset/ETHPy150Open anandology/pyjamas/library/pyjamas/ui/CustomButton.py/Face.getFaceID