Python Learning--Shades of copy

1. For numbers and strings, assignments, shallow copies, and deep copies are meaningless because they always point to the same memory address. 
>>> Import Copy
# ######### number, string #########
>>> N1 = 123
>>> Print (ID (N1))

# # # Assignment # #
>>> N2 = N1
>>> Print (ID (n2))

# # # Light Copy # #
>>> N2 = copy.copy (n1)
>>> Print (ID (n2))

# # # Deep Copy # #
>>> n3 = copy.deepcopy (N1)
>>> Print (ID (n3))

2. For dictionaries, Ganso, and lists, the changes in the memory address of the assignment, the shallow copy, and the deep copy are different. 
assignment: Just create a variable that points to the original memory address 
>>> n1 = {"K1": "Hu", "K2": 123, "K3": ["hh", 456]}
>>> N2 = N1

Shallow copy: Only additional first-tier data is created in memory but is worth the same address 
>>> Import Copy
>>> n1 = {"K1": "Hu", "K2": 123, "K3": ["hh", 456]}
>>> N2 = copy.copy (n1)
>>> Print (ID (N1))
5706496
>>> Print (ID (n2))
6270928

>>> Print (ID (n1[' k1 '))
6204824
>>> Print (ID (n2[' k1 '))
6204824

deep Copy: Recreate all the data in memory 
>>> Import Copy
>>> n1 = {"K1": "Hu", "K2": 123, "K3": ["hh", 456]}
>>> N2 = copy.deepcopy (n1)
>>> Print (ID (N1))
5706496
>>> Print (ID (n2))
6270808

>>> Print (ID (n1[' k1 '))
6204864
>>> Print (ID (n2[' k1 '))
500261040

Cases:
Dictionary dic ={' K1 ': [20,30], ' K2 ': [40,50], ' K3 ': [50,60]}, now need to update the dictionary saved in the new dictionary new_dic but does not change the original dictionary
>>> dic ={' K1 ': [20,30], ' K2 ': [40,50], ' K3 ': [50,60]}
Shallow copy: 
>>> new_dic = copy.copy (DIC)
>>> new_dic[' k1 '][0] = 100
#浅拷贝改变新字典的同时也改变了原来的字典 
>>> Print (New_dic)
{' K1 ': [100,30], ' K2 ': [40,50], ' K3 ': [50,60]}
>>> Print (DIC)
{' K1 ': [100,30], ' K2 ': [40,50], ' K3 ': [50,60]}

Deep Copy: 
>>> new_dic = copy.copy (DIC)
>>> new_dic[' k1 '][0] = 100
#深拷贝只改变新字典 
>>> Print (New_dic)
{' K1 ': [100,30], ' K2 ': [40,50], ' K3 ': [50,60]}
>>> Print (DIC)
{' K1 ': [20,30], ' K2 ': [40,50], ' K3 ': [50,60]}

python e-mail to send the source code:

1 #!/usr/bin/env python2 #-*-coding:utf-8-*-3 " "4 # @time: 2017/4/10 22:585 # @author: Huange6 # @version: 1.17 # @file: mail.py8 # @Software: Pycharm9 " "Ten #Coding:utf-8 #强制使用utf-8 encoded format One ImportSmtplib#loading the Smtplib module A  fromEmail.mime.textImportMimetext -  fromEmail.utilsImportformataddr -My_sender='********@163.com' #Sender e-mail account, for easy maintenance in the back, so write a variable the #my_user= ' ******* @qq. com ' #收件人邮箱账号, in order to be easy to maintain back, so write a variable - defMail (my_user):#user as formal parameter -ret=True -     Try: +Content =" " - Hello world! + SMTP (Simple Mail Transfer Protocol) is simply a message transfer protocol, which is a set of rules for sending mail from the source address to the destination. A It is the way to control the transfer of letters.  at         " " -Msg=mimetext (Content,'Plain','Utf-8') -msg[' from']=FORMATADDR (["Brother Huan", My_sender])#corresponding sender's mailbox nickname in parentheses, sender's email account -msg[' to']=FORMATADDR (["a misty rain", My_user])#corresponding recipient mailbox nickname in parentheses, Recipient's email account -msg['Subject']="python mail test" #the subject of the message, it can also be said to be a title -  inServer=smtplib. SMTP ("smtp.163.com", 25)#SMTP server in the sender's mailbox, port is -Server.login (My_sender,"Email Password")#the corresponding in parentheses is the sender's email account, email password toServer.sendmail (my_sender,[my_user,],msg.as_string ())#the corresponding in parentheses is the sender's mailbox account, the recipient's email account, the email +Server.quit ()#This is the meaning of closing the connection. -     exceptException as E:#if the statement in the try is not executed, the following ret=false is executed the         Print(e) *ret=False $     returnretPanax Notoginseng  -Ret=mail ('******* @qq. com')#actual Parameters the ifret: +     Print("OK")#If the send is successful, it will return OK, wait 20 seconds or so to receive the message A Else: the     Print("filed")#returns filed if the send fails

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PS: Use 163 mailbox as a mailbox when you need to log in to 163 mailbox in Settings, open the SMTP server!

Python Learning--Shades of copy