[已解决]为什么打印的值是None

easyboy

1. [1, 2, 3, 3, 3, 3].extend([i for i in range(4, 100)])

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是因为extend无返回值嘛

最佳答案

月排行榜 / 总排行榜

逃兵

2021-7-25 11:35:47

对，extend无返回值
需要先将列表赋值给变量

1. >>> a = [1, 2, 3, 3, 3, 3]
   
2. >>> a.extend([i for i in range(4, 100)])
   
3. >>> a
   
4. [1, 2, 3, 3, 3, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]

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逃兵

对，extend无返回值
需要先将列表赋值给变量

1. >>> a = [1, 2, 3, 3, 3, 3]
   
2. >>> a.extend([i for i in range(4, 100)])
   
3. >>> a
   
4. [1, 2, 3, 3, 3, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]

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柿子饼同学

嗯嗯, 她不会返回的

1. >>> [1, 2, 3].extend([4, 5])
   
2. >>> print([1, 2, 3].extend([4, 5]))
   
3. None
   
4. >>>

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