lis = [11,22,33,44,55]
# for i in range(len(lis)):
# print(i) # i = 0 i = 1 i = 2
# del lis[i]
# print(lis) # [11,22,33,44,55] [22, 44, 55] [22, 44]
#第一种
# lis = lis[::2]
# print(lis)
#第二种
# l1 = []
# for i in lis:
# if lis.index(i) % 2 == 0:
# l1.append(i)
# lis = l1
# print(lis)
# lis = [11,22,33,44,55]
# # for i in range(len(lis)-1,-1,-1):
# # if i % 2 == 1:
# # print(i)
# # del lis[i]
# # print(lis)
# # print(lis)
# dic = dict.fromkeys([1,2,3],'春哥')
# print(dic)
# dic = dict.fromkeys([1,2,3],[])
# print(dic) # {1: [], 2: [], 3: []}
# dic[1].append('袁姐')
# print(dic)
# dic[2].extend('二哥')
# print(dic)
# l1 = []
# l2 = l1
# l3 = l1
# l3.append('a')
# print(l1,l2,l3)
# dic = {'k1':'v1','k2':'v2','a3':'v3'}
# dic1 = {}
#
# for i in dic:
# if 'k' not in i:
# dic1.setdefault(i,dic[i])
# dic = dic1
# print(dic)
# l = []
# for i in dic:
# if 'k' in i:
# l.append(i)
# for i in l:
# del dic[i]
# print(dic)
# 转化成bool值
# 0 '' [] () {} set()
#元祖 如果元祖里面只有一个元素且不加,那此元素是什么类型,就是什么类型。
# tu1 = (1)
# tu2 = (1,)
# print(tu1,type(tu1))
# print(tu2,type(tu2))
# tu1 = ([1])
# tu2 = ([1],)
# print(tu1,type(tu1))
# print(tu2,type(tu2))
# dic = dict.fromkeys([1,2,3,],3)
# dic[1] = 4
# print(dic)
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# 赋值运算
# l1 = [1,2,3]
# l2 = l1
# l1.append('a')
# print(l1,l2)
#copy
# l1 = [1,2,3]
# l2 = l1.copy()
# print(l1,l2)
# print(id(l1),id(l2))
# l2.append('a')
# print(l1,l2)
# l1 = [1,2,[4,5,6],3]
# l2 = l1.copy()
# print(l1,id(l1))
# print(l2,id(l2))
# l1.append('a')
# print(l1,l2)
# l1[2].append('a')
# print(l1,l2)
# print(id(l1[2]))
# print(id(l2[2]))
import copy
# l1 = [1,2,[4,5,6],3]
# l2 = copy.deepcopy(l1)
# print(l1,id(l1))
# print(l2,id(l2))
# l1[2].append('a')
# print(l1,l2)
# l1 = [1,[1],2,3,4]
# l2 = l1[:]
# l1[1].append('a')
#l2 的结果是什么?
# print(l1,id(l1))
# print(l2,id(l2))
# print(l1[1] is l2[1])
# li = ['alex','taibai','wusir','egon']
# for i in li:
# print(li.index(i),i)
# for index,i in enumerate(li,1):
# print(index,i)