def test_list1(): assert (3 == count_evens([2, 1, 2, 3, 4]))
def test_list2(): assert (3 == count_evens([2, 2, 0]))
def test_list3(): assert (0 == count_evens([1, 3, 5]))
def test_count_evens_c(): assert count_evens([1, 3, 5]) == 0
def test_count_evens_b(): assert count_evens([2, 2, 0]) == 3
def test_count_evens_a(): assert count_evens([2, 1, 2, 3, 4]) == 3