Question

def countEvens(listOfInts):
    '''
    - Returns an integer value representing the number of even numbers that
    exist in listOfInts.
    - Return 0 if listOfInts is not a list type or if no even number exists
    in listOfInts.
    - Note: elements in listOfInts can contain any data type.
    '''
    return "stub"

# Tests for countEvens
def test_countEvens_1():
    assert countEvens([0,2,4]) == 3

def test_countEvens_2():
    assert countEvens([0,"2","Four", 6]) == 2

def test_countEvens_3():
    assert countEvens((0,2,4)) == 0

def test_countEvens_4():
    assert countEvens([-1,1,3,5,7]) == 0
    
def test_countEvens_5():
    assert countEvens([1.0,2.0,3.0,4.0,5.0,6.0,7.0,-2.0]) == 4

Answer 1

def countEvens(listOfInts):
    '''
    - Returns an integer value representing the number of even numbers that
    exist in listOfInts.
    - Return 0 if listOfInts is not a list type or if no even number exists
    in listOfInts.
    - Note: elements in listOfInts can contain any data type.
    '''
    count = 0
    if type(listOfInts) == list:
        for item in listOfInts:
            if (type(item) == int or type(item) == float) and item % 2 == 0:
                count += 1
    return count


# Tests for countEvens
def test_countEvens_1():
    assert countEvens([0, 2, 4]) == 3


def test_countEvens_2():
    assert countEvens([0, "2", "Four", 6]) == 2


def test_countEvens_3():
    assert countEvens((0, 2, 4)) == 0


def test_countEvens_4():
    assert countEvens([-1, 1, 3, 5, 7]) == 0


def test_countEvens_5():
    assert countEvens([1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, -2.0]) == 4