How to use the @uipath/angular/testing.Key.ArrowUp function in @uipath/angular

const searchInput = fixture.debugElement.query(By.css('.mat-input-element')).nativeElement;
                searchInput.value = customString;
                searchInput.dispatchEvent(EventGenerator.input());
                fixture.detectChanges();
                tick(SEARCH_DEBOUNCE);

                const customItem = fixture.debugElement.query(By.css('.custom-item'));

                expect(uiSuggest.items.length).toBeGreaterThan(0);
                expect(!!customItem).toBe(true);

                const itemContainer = fixture.debugElement.query(By.css('.item-list-container'));
                for (let i = 0; i <= uiSuggest.items.length; i++) {
                    itemContainer.nativeElement.dispatchEvent(
                        EventGenerator.keyDown(Key.ArrowUp),
                    );
                }
                fixture.detectChanges();
                tick(VIRTUAL_SCROLL_DEBOUNCE);

                expect(uiSuggest.activeIndex).toBe(-1);

                itemContainer.nativeElement.dispatchEvent(
                    EventGenerator.keyDown(Key.Enter),
                );
                fixture.detectChanges();
                tick(VIRTUAL_SCROLL_DEBOUNCE);

                expect(uiSuggest.value[0].text).toBe(customString);

                discardPeriodicTasks();