Python

Default parameters Argumentparser.set_defaults (**kwargs)Set_defaults () can set default values for some parameters>>> parser = Argparse. Argumentparser () >>> parser.add_argument (' foo ', type=int) >>> parser.set_defaults (bar=123, baz= '

1. Open the file:#!/usr/local/bin/python3.5filename="Fileop1.file"FD= open (filename,'a', encoding='Utf-8')#mode is read mode by default" "another way to open files with mode when the with code block finishes executing, the internal automatically

#FTP OperationImportFtplibhost='192.168.20.191'username='Ftpuser'Password='ftp123'file='1.txt'F= Ftplib. FTP (host)#instantiating an FTP objectF.login (username, password)#Login#Get current pathPwd_path =f.pwd ()Print("ftp current path:",

ListFirst define a listDeclaration ListList name =[value 1, value 2]list=[1,2,3,4,5]This is a list with five elements in the list (1,2,3,4,5)Show List ListingPrint ListOutput--[1,2,3,4,5]The subscript for the list starts at 0.Subscript = Length of

1 encoding of the string (encode) formatGB2312 GBK GB18030 UTF-8 ASCIIAmong the commonly used encoding formats areGB Series: GB18030 (GBK (GB2312)) (Windows common)International Standard: UNICODE16 UTF-8 (commonly used Linux/mac OS

Import RedisClass Myredis (object): Xiaohei = ' hahaha ' def __init__ (self, host, password= ", port=6379): Self.__host = Host Self.password = password Self.port = Port Self.__coon_redis () def __coon_redis (self)

First, the characteristics of the queue:1. FIFO 9 8 7 6 5 4 3 2 1 0 Last FirstSecond, class definition queueClass1. Instance PropertiesA.first nodeB.last nodeWhen each new

It took me about two weeks to familiarize myself with the basic grammar of Python3 before I started learning about spiders.Compared to the vb,python of my enlightening language, I have a deep understanding of the beauty. Life is short, I use

Product_list = [ ('MacBook', 9000), ('Kindle', 500), ('Tesla', 900000), (' Book', 100), ('Bike', 2000),]saving= Input ("Please input your money:") Shopping_car= []ifsaving.isdigit (): Saving=int (saving) whileTrue:#Print Product

Maybe we often use print to output information to the window, but when we have a lot of py files to run, the project is more thanThe larger the time, print is simply too low point. Then we can use the powerful logging module toOutput to a file in a

When I do the selenium element object stripping today (I put the element object into a variable of the tuple type, format: User = ("id", "x-auto-2")), encounter a tuple variable, and the STR string variable as a parameter to pass the value of the

1, how to achieve the Python list to the weight and maintain the original orderA: Then create a list, loop the original list element and determine if the current element is not in the new list, then add2, there are now two tuples ((' A '), (' B ')),

Import datetimeimport osimport timeimport pygamefrom pygame import mixerfrom pygame.locals Import usereventstopevent = use Revent + 1 #音乐停止事件h = 9 # time M = 26 # minutes Play_long = 60 * 10 # Play Long def Play (start): Paths = Os.listdir ('. ')

First, the regular Expression Foundation 1. IntroductionRegular expressions are not part of Python. Regular expressions are powerful tools for working with strings, with their own unique syntax and an independent processing engine, which may not be

# import Traceback# import Pymysql# Def Calc (A, B):# res = (A/b)# return Res### def main ():# money = input (' Enter how much: ')# months = input (' Also several months: ')# try:# res = calc (int (money), int (months))# except Zerodivisionerror as

How to read large files using PythonBackground When a text file is recently processed (the file size is about 2 GB ),memoryErrorErrors and files are too slow to read. Later, I found two fastLarge File ReadingThis article describes the two reading

Python monitoring keyboard input instance code, python monitoring keyboard input This article focuses on the python monitoring keyboard input code, such as OS, sys, and time. The specific implementation code is as follows: #! /Usr/bin/env python #-*-

Python implements the Decorator mode instance code, pythondecorator This article focuses on implementing the Decorator mode in python. The details are as follows. In general, the decorator is a function that accepts a function (or class) as a

Python 3.x Study Notes 13 (socket_ssh and socket _ file transfer), pythonsocket_ssh Ssh Server Import socket, osserver = socket. socket () server. bind ('localhost', 6666) server. listen () conn, addr = server. accept () while True: print ('Wait for

Simple Python variable parameters, python variable parameters 1 def total (a = 5, * numbers, ** phonebook): 2 print ('A', a) 3 # traverse all items in the tuples 4 for single_item in numbers: 5 print ('single _ item', single_item) 6 # traverse all