def test_interleave():
assert interleave([1, 2, 3, 4, 5]) == [1, 2, 3, 4, 5]
assert interleave() == []
assert interleave([1, 3], [2, 4]) == [1, 2, 3, 4]
assert interleave(repeat(1), [2, 4]) == [1, 2, 1, 4]
assert take(5, interleave(powers_of(2), powers_of(3))) == [1, 1, 2, 3, 4]
assert take(5, apply(interleave, map(powers_of, [2, 3]))) == [1, 1, 2, 3, 4]
def test_apply():
assert apply(plus) == 0
assert apply(plus, [1, 2, 3]) == 6
assert apply(concat, [[1, 2, 3], [4, 5, 6]]) == [1, 2, 3, 4, 5, 6]
def test_partial():
assert partial(plus)(1, 2, 3) == 6
assert partial(plus, 1)(2, 3) == 6
assert partial(take_last, 2)([1, 2, 3, 4]) == [3, 4]
assert apply(partial, [plus, 1, 2, 3])() == 6
