# your code goes here
mas = [1,2,3,4,5,6,7,8,9,10]
mas= [j for i in zip(mas[1::2], mas[::2]) for j in i]
print(mas)
IyB5b3VyIGNvZGUgZ29lcyBoZXJlCm1hcyA9IFsxLDIsMyw0LDUsNiw3LDgsOSwxMF0KbWFzPSBbaiBmb3IgaSBpbiB6aXAobWFzWzE6OjJdLCBtYXNbOjoyXSkgZm9yIGogaW4gaV0KcHJpbnQobWFzKQ==
[2, 1, 4, 3, 6, 5, 8, 7, 10, 9]