def same_direction(l1, l2):
    return all((x > 0) == (y > 0) for x, y in zip(l1, l2))
print(same_direction([1, 2, 3], [3, 7, 9]))
print(same_direction([-1, 2, 3], [1, 2, 3]))
print(same_direction([-1, 2, 3], [-1, 2, 3]))
how to know values at the same index in 2 lists in python are the same in positive or negative?