Python：连接列表的字符串变量

Question

我正在尝试修改Python中列表的所有元素：

magicians = ['harry potter', 'scamander', 'snape']

for magician in magicians:      
    magician = 'the Great ' + magician

print(magicians)

但它返回原始列表：

['harry potter', 'scamander', 'snape']

请您一步一步地向我解释一下吗？ 这可能是你见过的一个非常愚蠢的问题。我真的很抱歉。

Answer 1

您只是在改变循环范围中的元素。相反，使用元素索引重新分配：

magicians = ['harry potter', 'scamander', 'snape']

for i, magician in enumerate(magicians):      
   magician = 'the Great ' + magician
   magicians[i] = magician

print(magicians)

输出：

['the Great harry potter', 'the Great scamander', 'the Great snape']

但是，使用列表理解要短得多：

magicians = ['harry potter', 'scamander', 'snape'] 
new_magicians = ['the Great {}'.format(i) for i in magicians]

输出：

['the Great harry potter', 'the Great scamander', 'the Great snape']

在问题的范围内，甚至不需要循环：

final_data = ("the Great {}*"*len(magicians)).format(*magicians).split('*')[:-1]

Answer 2

列表理解更多是 pythonic 。

magicians = ['harry potter', 'scamander', 'snape']

great_magicians = ['the Great {}'.format(magician) for magician in magicians]

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