PIP related commands

1. View package information （ Include its dependent packages ）

pip show numpy

2. Check the versions of a package

pip install numpy==

3. Save the list to the specified file

 pip freeze > requiremnets.txt

4. Check compatibility
Verify whether the installed libraries have compatibility dependencies

pip check package-name

5.pip install

mock-django~=0.6.10

This means that it will choose the latest version of the package , Greater than or equal to 0.6.10, But it's still 0.6.* edition , So I won't download, for example 0.7.0. If package maintainers respect semantic versioning （ This indicates that major changes should only occur in major releases ）, It ensures that you get a safe fix but maintain backward compatibility .
https://stackoverflow.com/questions/39590187/in-requirements-txt-what-does-tilde-equals-mean