Using url tag and reverse() function, you can avoid hard-coding urls in template html files and views. So that even if the url path changes, it has no effect on templates and views source code. In fact, in the template view, if you want to get the currently accessed url, it’s more convenient to use …

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There are three functions in Python to remove one string’s head and tail characters and the blank characters, they are strip, lstrip and rstrip. strip : Used to remove both head and tail characters and blank characters (includes \n, \r, \t,’   ‘). lstrip : Used to remove head characters and blank characters (includes \n, …

How To Use String Truncation Function strip(), lstrip(), And rstrip() In Python3 Read More »

The default Python version under CentOS is 2.6 or 2.7, and now more and more modules support Python 3, so it is very necessary to install a Python 3 in CentOS. Instead of upgrading Python 2 to Python 3, we’re talking about installation, where Python 2 and Python 3 coexist. If you want to upgrade …

How To Compile And Install Python3 From Source Code In CentOS Read More »

The difference between __new__ and __init__ is mainly focus on self distinction and new-style and old-style python class definition. This article will show their difference with examples.

1. Question. According to the official document tutorial of Django project, i meet below problems in the chapter “Advanced tutorial: How to write reusable apps”. Install django-polls to MySite as directed. pip –user install /Users/john/django-polls/dist/django-polls-0.1.tar.gz Run Django server after install successfully. python manage.py runserver Browse url http://127.0.0.1:8000/polls/ in a web browser and returns an error. …

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1. Question. As the article title said, every Django version upgrade on exist project need a lot of re-install and re-compile. That make too much trouble. Is there any easy way to do it? 2. Answer 1. First use pip freeze to export current python library to file a. Then install the exported library in new …

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1. Question. Now there is a project, the old version is developed in Django 1.5, the new version is developed in Django version 1.7, the new and old versions need to be developed in parallel for some time in the near future. The question is how to install 1.5 and 1.7 versions of Django simultaneously …

How To Install Django Version 1.5 And 1.7 On One Linux Simultaneously Read More »

Python built-in functions are functions provided by python for you to use directly, such as print and input, etc. As of python version 3.6.2, a total of 68 built-in functions are provided. Today, let’s take a look at python’s built-in functions as shown in the figure below.

For a Python list or tuple object, we can go through it via a for loop, which we call iteration. In Python, iteration is done by for… in, whereas in many languages, such as C, iteration lists are done by subscripts, such as below Java code.