There are 2 ways you may install any package with version:- A). pip install -Iv package-name == version B). pip install -v package-name == version
For A
Here, if you're using -I option while installing(when you don't know if the package is already installed) (like 'pip install -Iv pyreadline == 2.* 'or something), you would be installing a new separate package with the same existing package having some different version.
For B
2.and then see what's already installed by pip list
3.if the list of the packages contain any package that you wish to install with specific version then the better option is to uninstall the package of this version first, by pip uninstall package-name
4.And now you can go ahead to reinstall the same package with a specific version, by pip install -v package-name==version e.g. pip install -v pyreadline == 2.*