 
         let returnValue = dataSource.collectionView(
             collectionView,
-            viewForSupplementaryElementOfKind: UICollectionElementKindSectionHeader,
+            viewForSupplementaryElementOfKind: UICollectionView.elementKindSectionHeader,
             at: IndexPath(item: 0, section: 0)
         )
         XCTAssertEqual(returnValue, sentinel)


        let returnValue = dataSource.collectionView(
            collectionView,
            viewForSupplementaryElementOfKind: UICollectionElementKindSectionHeader,
            at: IndexPath(item: 0, section: 0)
        )
        XCTAssertEqual(returnValue, sentinel)


        let returnValue = dataSource.collectionView(
            collectionView,
            viewForSupplementaryElementOfKind: UICollectionView.elementKindSectionHeader,
            at: IndexPath(item: 0, section: 0)
        )
        XCTAssertEqual(returnValue, sentinel)
