Upgrade a package for a bunch of virtualenvs

update-virtualenvs.zsh

#!/bin/zsh
autoload -U colors && colors

if [[ -z $1 ]]; then
    read "upgradePackage?Which pacakge to upgrade? "
else
    upgradePackage=$1
fi

VIRTUALENV_INSTALLS="/var/virtualenvs"
VIRTUALENV_HOMES=(`find $VIRTUALENV_INSTALLS -maxdepth 1 -type d`)

for virtualenv in $VIRTUALENV_HOMES; do
    if [[ -e "$virtualenv/bin/activate" ]]; then
        echo "Working on ${fg[blue]}${virtualenv}${reset_color}"
        source $virtualenv/bin/activate
        pip install --upgrade $upgradePackage
        deactivate
    fi
done