def test_maxNum_5(): assert maxNum([4,4,"4",3]) == None
def test_maxNum_4(): assert maxNum("1,2,3") == None
def test_maxNum_2(): assert maxNum([4,3,12,2]) == 12
def test_maxNum_3(): assert maxNum([-1.1,-1.2,-3.3,-2.2]) == -1.1
def test_maxNum_1(): assert maxNum([]) == None