擅长:python、mysql、java
<p>您正在将字符串添加到一起。只需附加两次</p>
<pre><code>blist = []
def double_list(alist):
for i in alist:
blist.append(i)
blist.append(i)
return blist
print('original list: ',double_list(['how','are','you?']))
print('double list: ',blist)
</code></pre>
<p>我相信有更好的方法,但这有助于更好地理解解决方案</p>