python集合set和创建对象的复制方法是什么

集合set

输入：

bri = set(['brazil', 'russia', 'india'])

print('india' in bri) 

print('usa' in bri )

bric = bri.copy() 

bric.add('china') 

print( bric.issuperset(bri) )

bri.remove('russia') 

print( bri & bric )

# OR bri.intersection(bric) 

输出：

创建对象的复制操作

输入：

#!/usr/bin/python 

# Filename: reference.py 

print('Simple Assignment') 

shoplist = ['apple', 'mango', 'carrot', 'banana']mylist = shoplist 

# mylist is just another name pointing to the sameobject! 

del shoplist[0] 

# I purchased the first item, so I remove it from thelist 

print('shoplist is', shoplist) 

print('mylist is', mylist) 

# notice that both shoplist and mylist both print the same list without 

# the 'apple' confirming that they point to the same object 

print('Copy by making a full slice') 

mylist = shoplist[:] # make a copy by doing a full slice 

del mylist[0] 

# remove first item 

print('shoplist is', shoplist) 

print('mylist is', mylist) 

# notice that now the two lists are different

输出：