A simple script to fix and reinstall all modules for each virtualenv of a user after upgrading whole system Python. https://blog.m157q.tw/posts/2015/10/07/fix-virtualenv-after-an-upgrade-of-python/

fix_virtualenvs.sh

#!/usr/bin/env bash

VIRTUALENVS_ROOT_DIR="${HOME}/.virtualenvs"
ACTIVE_SH_PATH="/bin/activate"

for dir in `find ${VIRTUALENVS_ROOT_DIR} -type d -maxdepth 1`
do
    if [[ ${dir} == ${VIRTUALENVS_ROOT_DIR} ]]; then
        continue
    fi

    source ${dir}${ACTIVE_SH_PATH}

    ENV_PATH="$(dirname "$(dirname "$(which pip)")")"
    SYSTEM_VIRTUALENV="$(which -a virtualenv|tail -1)"

    echo
    echo "Ensure the root of current virtualenv:"
    echo "    $ENV_PATH"
    read -p "Say no if you are not sure (y/N) " -n 1 -r
    echo
    if [[ $REPLY =~ ^[Yy]$ ]]; then

        read -p "Reinstall all packages of this virtualenv after upgraded? (y/N) " -n 1 -r


        if [[ $REPLY =~ "^[Yy]$" ]]; then
            echo "Dump pip freeze for current virtualenv into requirements.temp"
            pip freeze > requirements.temp
        fi

        VIRTUALENV_PYTHON_VERSION=`python --version`
        echo "Removing old symbolic links......"
        find "$ENV_PATH" -type l -delete -print

        echo "Creating new symbolic links......"
        echo ${VIRTUALENV_PYTHON_VERSION}
        if [[ $VIRTUALENV_PYTHON_VERSION =~ "Python 2" ]]; then
            echo "Use Python 2 environment for this virtualenv"
            $SYSTEM_VIRTUALENV "$ENV_PATH" --python=python2
        elif [[ $VIRTUALENV_PYTHON_VERSION =~ "Python 3" ]]; then
            echo "Use Python 3 environment for this virtualenv"
            $SYSTEM_VIRTUALENV "$ENV_PATH" --python=python3
        else
            echo "Unknown Python version of this virtualenv"
        fi

        if [[ $REPLY =~ "^[Yy]$" ]]; then
            echo "Reinstall modules from previous dumped pip freeze result."
            pip install -r requirements.temp

            echo "Remove requirements.temp"
            rm requirements.temp
        fi
    fi

    deactivate
done

echo "Done!"