Python

This article brings you the content is about Python in the Future Module introduction (code), there is a certain reference value, the need for friends can refer to, I hope to help you. Concurrent.futures Module The main features of the module are

This article brings you the content is about how Python implementation yang Hui triangle (code), there is a certain reference value, the need for friends can refer to, I hope to help you. The Yang Hui Triangle Yang Hui is defined as follows:

First look at the Pycharm input file handle, how to display his definitionf = open (' student_msg ', encoding= ' utf-8 ', mode= ' A + ') # Opens a file, assigns a value to FThe print (Type (f), F) # f file handle belongs to a class called Input and

First, the TCP protocolPurpose: Reliable transmission, TCP packet has no length limit, theoretically can be infinitely long, but in order to ensure the efficiency of the network, usually the length of TCP packets will not exceed the length of IP

Map (func, *iterables)---Map objectMap () is a Python built-in high-order function that receives a function func and a list (*iterables), and by the function func on each element of the list, gets a new list and returns.For example, for list [1, 2, 3

Recently found using BeautifulSoup to parse Web page HTML while writing crawlers.Using the parse result fragment is:Dead Waiter 2/DP22018-05-18 (USA)/Ryan Reynolds/Josh Brolin/Marmalade Na Bakarin/Julian Dinison/Sasha Bates/T. J. Miller/Leslie Geses/

#以下是我自己在联系列表中所编写的语句:names=["Zangsan", ' Lisi ', ' Wangermazi ', ' Xiaoliuzi ', ' dabiaoge ', ' ox Erbiaodi ']#----------0--------1---------2---------------3----------4---------5--------Print (names[2]) #简单取值#取lisi和wangermaziPrint

There are several ways to judge equality:= = , is, isinstance ,issubclass ,operator 模块。= = : Two object content is equal.>>> a = [22,44]>>> B = [22,44]>>> a==bTrue>>> C = 1>>> d = 2>>> c = = dFalse is: Whether the object occupies the same memory

#coding: GBKFrom XLRD import Open_workbookImport mockImport xlrdImport XLWTFrom xlutils.copy Import copyImport OSAcct = MOCK.ACCT_IDdata = Mock.acct_dataStart_time = Mock.start_timePrint Start_timeEnd_time = Mock.end_time5Haoshi = Mock.result_endREQ_

Summary of the mainstream web frameworka socketb 路由关系c 模板字符串替换（模板语言）主流web框架djange a用别人的 b自己写 c自己写flask a用别人的 b自己写 c用别人的(jinja2)tornado a自己写 b自己写 c自己写Create a Django1DjangoModule Installation 2CreateDjangoProjectDjango-adminStartprojectProject

Single-Case modeMultiple instantiation results point to the same instanceSingle-instance mode implementation methodWay One:1 ImportSettings2 3 classMySQL:4 __instance=None5 6 def __init__(self, IP, port):7Self.ip =IP8Self.port =Port9 Ten

__contains__ (): Called on class instance using in, not in operationClass A (object):def __init__ (Self,num):Self.num=numdef __contains__ (Self,item):Print (' __contains__:%s is in? '% item)If Item = 0:Return Trueelse:Return FalseIf __name__== '

API one, the number of characters in a string Str.count (Sub, start= 0,end=len (String)) Args Annotations Sub Substring of search Start The location where the string

1 #Coding=utf-82 fromSeleniumImportWebdriver3 fromTimeImportSleep4 Importkeyword5 fromSelenium.webdriver.common.keysImportKeys6 fromSelenium.webdriver.support.waitImportwebdriverwait7 fromSelenium.webdriver.support.uiImportSelect8 ImportCSV9

Thread Pool ********Python standard module--Concurrent.futures1The introduction of the Concurrent.futures module provides a highly encapsulated asynchronous calling interface Threadpoolexecutor: The thread pool, which provides an asynchronous call

Tuple is also a sequence, but the same list and dict is different, once a tuple is defined, it cannot be modified (add, delete, change), only the tuple query.Usually we say the query, no other than this kind of query:1, know the small location of

I. Python2ASCII-encoded by default in Python2str= ' Hello World ' gbk_to_unicode=str.decode (' GBK ') #将gbk解码为unicodeprint (Gbk_to_unicode) unicode_to_utf-8=gbk_to_ Unicode.encode (' Utf-8 ') #将unicode编码为utf -8print (unicode_to_utf-8)Two.

In practice, there are times when we cannot guarantee that the program we write is perfect. For example, the intention of our program is: the user enters the input box number, and carries on the mathematical operation, even if we remind the user to

First, exception handlingIn the process of running the program, you will always encounter a variety of errors. Program An error stopped running, then we can not let the program stop running it, this time we need to catch the exception, by catching

Create a projectFirst go to an empty directory, open the Operation command line, enter:django-admin startproject 项目名称Establishing a database connectionGo to the project directory to open the settings.py file, modify the following fieldsDATABASES = {