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‘’’
str int
‘’’
str
# s = ‘’
# print(s.isspace())
int
‘’’
list:
‘’’
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。