python中列表如何去重？

方法一: 使用内置set方法来去重

>>> lst1 = [2, 1, 3, 4, 1]

>>> lst2 = list(set(lst1))

>>> print(lst2)

[1, 2, 3, 4]

方法二: 使用字典中fromkeys()的方法来去重

>>> lst1 = [2, 1, 3, 4, 1]

>>> lst2 = {}.fromkeys(lst1).keys()

>>> print(lst2)

dict_keys([2, 1, 3, 4])

方法三: 使用常规方法来去重

>>> lst1 = [2, 1, 3, 4, 1]

>>> temp = []

>>> for item in lst1:

if not item in temp:

   temp.append(item)

>>> print(temp)

[2, 1, 3, 4]

方法四: 使用列表推导来去重

>>> lst1 = [2, 1, 3, 4, 1]

>>> temp = []

>>> [temp.append(i) for i in lst1 if not i in temp]

[None, None, None, None]

>>> print(temp)

[2, 1, 3, 4]

方法五: 使用sort函数来去重

>>> lst1 = [2, 1, 3, 4, 1]

>>> lst2.sort(key=lst1.index)

>>> print(lst2)

[2, 1, 3, 4]

方法六: 使用sorted函数来去重

>>> lst1 = [2, 1, 3, 4, 1]

>>> lst2 = sorted(set(lst1), key=lst1.index)

>>> print(lst2)

[2, 1, 3, 4]