Flattening: 0
Flattening: {0, 0, 0, 0}
Flattening: 0
Flattening: {1, 2, 3}
Flattening: {1, 2, 3, 4, 5, 6, 7, 8, 9}
List to array: [1, 2, 3, 4, 5]
Array to list: {1, 2, 3, 4, 5}