How to use the @lwc/features.ENABLE_REACTIVE_SETTER function in @lwc/features

const vmBeingRendered = getVMBeingRendered();
                assert.invariant(
                    !isInvokingRender,
                    `${vmBeingRendered}.render() method has side effects on the state of ${vm}.${toString(
                        key
                    )}`
                );
                assert.invariant(
                    !isUpdatingTemplate,
                    `Updating the template of ${vmBeingRendered} has side effects on the state of ${vm}.${toString(
                        key
                    )}`
                );
            }
            if (set) {
                if (features.ENABLE_REACTIVE_SETTER) {
                    let ro = vm.oar[key as any] as AccessorReactiveObserver;
                    if (isUndefined(ro)) {
                        ro = vm.oar[key as any] = new AccessorReactiveObserver(vm, set);
                    }
                    // every time we invoke this setter from outside (through this wrapper setter)
                    // we should reset the value and then debounce just in case there is a pending
                    // invocation the next tick that is not longer relevant since the value is changing
                    // from outside.
                    ro.reset(newValue);
                    ro.observe(() => {
                        set.call(this, newValue);
                    });
                } else {
                    set.call(this, newValue);
                }
            } else if (process.env.NODE_ENV !== 'production') {