<p>下面代码的执行结果是：( )<br/> ls = ["2020", "20.20", "Python"]<br/> ls.append(2020)<br/> ls.append([2020, "2020"])<br/> print(ls)</p>
<p> ['2020', '20.20', 'Python', 2020]</p>
<p> ['2020', '20.20', 'Python', 2020, [2020, '2020']]</p>
<p> ['2020', '20.20', 'Python', 2020, ['2020']]</p>
<p> ['2020', '20.20', 'Python', 2020, 2020, '2020']</p>
