python 列表去重的几种方法

1

a = [,,,,,,,,,,]
a1 = []
for i in a:
    if i not a1:
        a1.append(i)
    else:
        continue

2

a = [,,,,,,,,,]
a1 = set(a)

3

a = [,,,,,,,,,,]
for i in a:
    while a.count(i)>:
        del a[a.index(i)]

4

import itertools

a = [,,,,,,,]
a1 = []
for i in itertools.groupby(a):
    a1.append(i)