def test_concatv():
assert list(concatv([], [], [])) == []
assert list(take(5, concatv(["a", "b"], range(1000000000)))) == ["a", "b", 0, 1, 2]
def test_iterate():
assert list(itertools.islice(iterate(inc, 0), 0, 5)) == [0, 1, 2, 3, 4]
assert list(take(4, iterate(double, 1))) == [1, 2, 4, 8]
def test_take():
assert list(take(3, "ABCDE")) == list("ABC")
assert list(take(2, (3, 2, 1))) == list((3, 2))
def test_take():
assert list(take(3, 'ABCDE')) == list('ABC')
assert list(take(2, (3, 2, 1))) == list((3, 2))
def test_concatv():
assert list(concatv([], [], [])) == []
assert (list(take(5, concatv(['a', 'b'], range(1000000000)))) ==
['a', 'b', 0, 1, 2])
def test_take():
assert list(take(3, 'ABCDE')) == list('ABC')
assert list(take(2, (3, 2, 1))) == list((3, 2))
def test_concatv():
assert list(concatv([], [], [])) == []
assert (list(take(5, concatv(['a', 'b'],
range(1000000000)))) == ['a', 'b', 0, 1, 2])
