这种方式是在遍历整个list的基础上，将第一个出现的元素添加在新的列表中。
# Python 3 code to demonstrate
# removing duplicated from list
# using naive methods
# initializing list
test_list = [1, 3, 5, 6, 3, 5, 6, 1]
print ("The original list is : " + str(test_list))
# using naive method
# to remove duplicated
# from list
res = []
for i in test_list:
if i not in res:
res.append(i)
# printing list after removal
print ("The list after removing duplicates : " + str(res))
The original list is : [1, 3, 5, 6, 3, 5, 6, 1]
The list after removing duplicates : [1, 3, 5, 6]
这种方式实际上是第一种方法的简化版，它利用列表解析式，使用一行代码就可以替代上面的循环方式。
# Python 3 code to demonstrate
# removing duplicated from list
# using list comprehension
# initializing list
test_list = [1, 3, 5, 6, 3, 5, 6, 1]
print ("The original list is : " + str(test_list))
# using list comprehension
# to remove duplicated
# from list
res = []
[res.append(x) for x in test_list if x not in res]
# printing list after removal
print ("The list after removing duplicates : " + str(res))
The original list is : [1, 3, 5, 6, 3, 5, 6, 1]
The list after removing duplicates : [1, 3, 5, 6]
这种方式是最流行的方法来去除列表中的重复元素。但该方法的最大的一个缺点就是使用过后列表中元素的顺序不再继续保持与原来一致了。
# Python 3 code to demonstrate
# removing duplicated from list
# using set()
# initializing list
test_list = [1, 5, 3, 6, 3, 5, 6, 1]
print ("The original list is : " + str(test_list))
# using set()
# to remove duplicated
# from list
test_list = list(set(test_list))
# printing list after removal
# distorted ordering
print ("The list after removing duplicates : " + str(test_list))
The original list is : [1, 5, 3, 6, 3, 5, 6, 1]
The list after removing duplicates : [1, 3, 5, 6]
该方法是在列表解析式的基础上利用枚举来去除重复元素。通过检查元素是否已经在列表中存在从而将其略过。这种方法可以保持列表中的元素顺序不会改变。
# Python 3 code to demonstrate
# removing duplicated from list
# using list comprehension + enumerate()
# initializing list
test_list = [1, 5, 3, 6, 3, 5, 6, 1]
print ("The original list is : " + str(test_list))
# using list comprehension + enumerate()
# to remove duplicated
# from list
res = [i for n, i in enumerate(test_list) if i not in test_list[:n]]
# printing list after removal
print ("The list after removing duplicates : " + str(res))
The original list is : [1, 5, 3, 6, 3, 5, 6, 1]
The list after removing duplicates : [1, 5, 3, 6]
这是完成特殊任务中最快的方法，利用 collections.OrderedDict.fromkeys()。它先是将列表中的重复项移除并返回一个字典，最后转换成列表。这种方法对于字符串也可以进行处理。
# Python 3 code to demonstrate
# removing duplicated from list
# using collections.OrderedDict.fromkeys()
from collections import OrderedDict
# initializing list
test_list = [1, 5, 3, 6, 3, 5, 6, 1]
print ("The original list is : " + str(test_list))
# using collections.OrderedDict.fromkeys()
# to remove duplicated
# from list
res = list(OrderedDict.fromkeys(test_list))
# printing list after removal
print ("The list after removing duplicates : " + str(res))
The original list is : [1, 5, 3, 6, 3, 5, 6, 1]
The list after removing duplicates : [1, 5, 3, 6]
对于多维列表（列表嵌套）中的重复元素去除。这里假设列表中元素（也是列表）它们具有相同的元素（但不一定顺序相同）都被当做重复元素。那么下面使用 set() + sorted() 方法来完成任务。
# Python3 code to demonstrate
# removing duplicate sublist
# using set() + sorted()
# initializing list
test_list = [[1, 0, -1], [-1, 0, 1], [-1, 0, 1],
[1, 2, 3], [3, 4, 1]]
# printing original list
print("The original list : " + str(test_list))
# using set() + sorted()
# removing duplicate sublist
res = list(set(tuple(sorted(sub)) for sub in test_list))
# print result
print("The list after duplicate removal : " + str(res))
The original list : [[1, 0, -1], [-1, 0, 1], [-1, 0, 1], [1, 2, 3], [3, 4, 1]]
The list after duplicate removal : [(-1, 0, 1), (1, 3, 4), (1, 2, 3)]
也可以利用 set() + map() + sorted()
# Python3 code to demonstrate
# removing duplicate sublist
# using set() + map() + sorted()
# initializing list
test_list = [[1, 0, -1], [-1, 0, 1], [-1, 0, 1],
[1, 2, 3], [3, 4, 1]]
# printing original list
print("The original list : " + str(test_list))
# using set() + map() + sorted()
# removing duplicate sublist
res = list(set(map(lambda i: tuple(sorted(i)), test_list)))
# print result
print("The list after duplicate removal : " + str(res))
The original list : [[1, 0, -1], [-1, 0, 1], [-1, 0, 1], [1, 2, 3], [3, 4, 1]]
The list after duplicate removal : [(-1, 0, 1), (1, 3, 4), (1, 2, 3)]
Python – Ways to remove duplicates from list: https://www.geeksforgeeks.org/python-ways-to-remove-duplicates-from-list/
[2]Python | Remove duplicates from nested list: https://www.geeksforgeeks.org/python-remove-duplicates-from-nested-list/?ref=rp
卓大大，请问今年的室内组，会有这样的光吗？
回复： 在一些赛区这种情况是有可能的。
卓大大，投稿。室外电磁赛道。
卓老师直角可以像这样连续倒车吗?
回复： 这是允许的。
卓大，单车省赛赛道会是前几天邀请赛那样的吗 ？卓大比赛的坡道会比今天黑龙江邀请赛的坡道大吗？
回复： 自从看到黑龙江省赛的这个室外单车比赛现场，也解决了我的一个大难题。这个赛道足够大，满足“拉力赛”的要求。元素足够丰富。同时又通过了比赛的验证，所以这个场地应该是我们暑期分赛区赛场的原型了。需要感谢哈工大组织的这次黑龙江省赛给出的设计方案。只是坡道稍微矮了点。
那我要抓紧时间调了。
