after ranger quits, cd to the chosen directory.

ranger.py

ranger() {
    tempfile='/tmp/chosendir'
    /usr/bin/ranger --choosedir="$tempfile" "${@:-$(pwd)}"
    test -f "$tempfile" &&
    if [ "$(cat -- "$tempfile")" != "$(echo -n `pwd`)" ]; then
        cd -- "$(cat "$tempfile")"
    fi
    rm -f -- "$tempfile"
}