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If/else/elif, For/while, try/except scope of internal variables Python For Python, if/elif/else/try/except For/while does not change its scope. Variables that are defined within them, can be accessed externally. The following code: A = 2 if a = =

variablePython has a slightly different approach to most other computer languages, assigning values directly to variables without defining which data type the variable belongs to, and it looks more like putting the name on top of the value before

1, control structure 1.1 piece branch 1.2 circulation 1.2.1 while loop 1.2.2 for loop 2, exception handling 2.1 Catch Exception 2.2 Produce exception 2.3 Custom exception 3, custom function 3.1 name and Docstrings 3.2 parameter and parameter split 3.

Redis is very popular in the current technology community. From a small personal project from Antirez to a standard in the memory data storage industry, Redis has come a long way.1. Stop using KEYS * Okay, it may not be a good way to start this

Variable scope (scope) is an easy place to drop holes in python.There are 4 scopes in Python, namely: L (local) local scope In functions outside of the E (enclosing) closure function G (Global) scope B (built-in)

Python 3 Program Development Guide (2nd edition revision)Directory 1 process-oriented programming Quick Start 2 Data Type 3 Combination Type 4 control structures and functions 5 Module 6 OOP 7 file Processing 8 Advanced Programming

Zen CentThe article has been collected, written too well, back up a copy of theAuthor: http://www.cnblogs.com/shangdawei/p/4058452.htmlIntroductionbelieve that some computer knowledge of friends should have heard of the "DLL." In particular, those

Here are some of the python practical tips and tools I've collected in recent years that I hope will help you.Swap variablesx = 6y = 5X, y = y, XPrint X>>> 5Print Y>>> 6If statement in rowPrint "Hello" if True else "world">>> HelloConnectionThe last

Python file operations It's a lot easier to do than files in Java,python.Python Gets the folder where the current file resides:Os.path.dirname (__file__)Wrote a tool class to generate files under the current folder, so it's easy toclass Util ():

Python basic Syntax (iii)--------------------------------------------the basic syntax of Python (ii)--------------------------------------------Vii. Object-Oriented programmingPython supports object-oriented programming, classes and objects are the

Python is simple and elegant, the library is rich and powerful, especially in the field of data analysis, has an important position.Here are some of the important, easy-to-forget knowledge points I learnedHow is python doing memory management?First

UrlerrorUrlerror Cause: Network is not connected (ie cannot surf the internet) Server does not exist We generally enclose and catch the corresponding exception through the try-except statement. Let's try it first:1 Import Urllib2 2

Lead: http://www.delphibbs.com/keylife/iblog_show.asp? Xid = 29323 By: 600666 Title: Delphi code specifications Keywords: Category: personal zone Confidentiality level: Public The purpose of this specification: to provide a unified and standard

  procedure GenerateJPEGfromBrowser(browser: iWebBrowser2;                                  jpegFQFilename: string; srcHeight:                                  integer; srcWidth: integer;                                  tarHeight: integer; tarWidth:

Then the first article continued to study. I. Classification of data Correct data: ID, gender, activity time are all three Put it in this file File1 = ' ruisi\\correct%s-%s.txt '% (Startnum, endnum) Data format for 293001 men 2015-5-1 19:17

This section here is mainly about Urlerror and httperror, and some of the handling of them. 1.URLError First explain the possible causes of Urlerror: Network is not connected, that is, the computer cannot surf the internet Cannot connect

Purpose Tests whether an object is a string Method The base class for the Python string is basestring, which includes the STR and Unicode types. You can generally use the following methods: The code is as follows: def isastring (anobj): Return

SQLite is an embedded database, and its database is a file. Since SQLite itself is written in C and small in size, it is often integrated into a variety of applications, even in iOS and Android apps. Python has built-in SQLite3, so using SQLite in

The last file update method used is the file method: VaRSfilename: string;Sin: string;BeginSin: = extractfilepath (application. exename) + 'Update. ini ';TryIf fileexists (SIN) thenBegin// File backupSfilename: = extractfilepath (application.

Abnormal The exception occurs when there are some abnormal conditions in your program. For example, when you want to read a file, and that file does not exist. Or when the program is running, you accidentally delete it. These conditions can be