Python virtual environment selector

pyenv.sh

function pyenv() {
    VIRTUALENVS_PATH=~/pyenvs

    # Procure env name. If it was supplied in an argument, use that
    if [[ "$1" != "" ]]
    then
        VIRTUALENV_NAME=$1
    else
        # Otherwise prompt the user for it
        VIRTUALENV_NAME=""

        echo "Python virtual environment selector"
        echo "Options: $(ls -h -C $VIRTUALENVS_PATH)"
        read -p "Virtualenv name: " VIRTUALENV_NAME
    fi

    # Generate path
    VIRTUALENV_PATH=$VIRTUALENVS_PATH/$VIRTUALENV_NAME/bin/activate

    # Check if the virtual environment with this name exists
    if [[ -f "$VIRTUALENV_PATH" ]]
    then
        # If yes, activate it it
        source $VIRTUALENVS_PATH/$VIRTUALENV_NAME/bin/activate
        echo "Activated virtual environment \"$VIRTUALENV_NAME\""
    else
        # Otherwise echo that it doesn't exist
        echo "Virtual environment \"$VIRTUALENV_NAME\" not found"
    fi
}