3.下面代码的执行结果是( )。>>>ls = ["2020", "20.20", "Python"] >>>ls.append(2020)>>>ls.append([2020, "2020"])>>>print(ls)
A. ['2020', '20.20', 'Python', 2020, [2020, '2020']]
B. ['2020', '20.20', 'Python', 2020, 2020, '2020']
C. ['2020', '20.20', 'Python', 2020]
D. ['2020', '20.20', 'Python', 2020, ['2020']]