What is a python virtual environment? Introduction to python virtual environment

This article brings you what is the python virtual environment? The introduction to the python virtual environment has certain reference value. Friends in need can refer to it. I hope it will be helpful to you.

What is Python's virtual environment

I remember when I was writing code in school, the version management system was not used at that time. In this case, if you want Do an experiment on your own small project but you don’t want to keep the test code after the experiment is completed. What should you do? The method is very simple, that is:

Directly copy the entire project

and then Do experiments on the newly copied project so that it will not interfere with the normal code. After the experiment is completed, just delete the copied project.

Essentially, the purpose of Python's virtual environment is the same as above. I hope you will not misunderstand the word "virtual". Python's virtual environment is nothing more than copying the system's Python running environment to a designated folder. The content in this folder is the so-called virtual environment. You can do experiments (write your Python code) in this copied environment without worrying about affecting other projects.

That is to say, each virtual environment is independent and isolated from each other. You can think of Python's virtual environment as an entire project copied directly for experiments in school.

Installation

In Python, the tool used to package the Python running environment in the copy system is virtualenv. Installation is also very simple.

$ pip install virtualenv

Usage

Create a virtual environment

After installing virtualenv, you can use it. I want to create a virtualenv called web Use the command in the virtual environment:

$ virtualenv web

After running this command, there will be a folder called web. When you open it, you will see that there is a complete Python running environment, including bin, include, lib, etc. You can modify these files at will without worrying about affecting other Python projects and the system's Python running environment.

Activate the virtual environment

Before using the virtual environment, you must tell the operating system: "Hi, operating system, I want to use Python under the web, do not affect other Python project", so how to tell the operating system. Use the command:

$ source web/bin/activate

After running this command, you will find that there will be a few more words in front of your command line, which are the commands of your virtual environment. These additional words tell you that the current Running code using Python in a virtual environment.

Exit the virtual environment

When you want to exit the virtual environment, you can use the following command to tell the operating system to let you out.

$ deactivate

After running this command, use Python installed in the system.

Isn’t it very simple?

What should you do if your Python project is developed and you no longer want to use this virtual environment? It's very simple, just delete it.

The above is the detailed content of What is a python virtual environment? Introduction to python virtual environment. For more information, please follow other related articles on the PHP Chinese website!