Python - Return array from array iteration

def x():
    return [[i, j]
            for i in [1, 2, 3]
            for j in [3, 4, 5]]

y = x()

for i in y:
    print(i[0], i[1])

Output:

1 3
1 4
1 5
2 3
2 4
2 5
3 3
3 4
3 5