Python中append和extend的區別

list.append(object) 向列表中添加一個對象object
list.extend(sequence) 把一個序列seq的內容添加到列表中

music_media = ['compact disc', '8-track tape', 'long playing record']
new_media = ['DVD Audio disc', 'Super Audio CD']
music_media.append(new_media)
print music_media
>>>['compact disc', '8-track tape', 'long playing record', ['DVD Audio disc', 'Super Audio CD']]

使用append的時候，是將new_media看作一個對象，整體打包添加到music_media對象中。

music_media = ['compact disc', '8-track tape', 'long playing record']
new_media = ['DVD Audio disc', 'Super Audio CD']
music_media.extend(new_media)
print music_media
>>>['compact disc', '8-track tape', 'long playing record', 'DVD Audio disc', 'Super Audio CD']

使用extend的時候，是將new_media看作一個序列，將這個序列和music_media序列合並，並放在其后面。