I. Introduction
In Python project development, each project is independent, so virtual environments are used , but the dependent packages and versions of each project are different.
For example: you need to take over a project that someone else has handed over to you, or you want to run a project written by yourself before, but the environment needs to be reconfigured, the dependencies must be downloaded again, and the version cannot be remembered. What should I do?
In fact, two pip commands can solve this problem well.
2. import dependencies
2.1 When we pull down a project on github , we can find that there is a requirements.txt
folder in it, which contains various dependencies of the project
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2.2 Open requirements.txt
, there are all dependent packages and versions
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2.3 Just enter the following commands in the terminal to install requirements.txt
the dependencies required by the project
pip install -r requirements.txt
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3. export dependency
3.1 As we all know, pip list
you can view the dependencies of the current project installation, but its format is not Dependency Packages == Versions
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3.2 It pip freeze
can be used to print Dependency Packages == Versions
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3.3 Then enter the following command in the terminal to export the above content and package it requirements.txt
and in
pip freeze >requirements.txt
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3.4 When you need to use it later, pip install -r requirements.txt
you can directly use the command to install the dependencies with one click
This article is reprinted from: https://www.cnblogs.com/xuexianqi/p/13329692.html