post_install() {
  /usr/bin/getent group nitrokey >/dev/null 2>&1 || usr/sbin/groupadd -r nitrokey &>/dev/null
  udevadm control --reload
  echo "Don't forget to add users to the nitrokey group."
}

post_upgrade() {
    post_install
}

post_remove() {
    if /usr/bin/getent group nitrokey >/dev/null 2>&1; then
        /usr/sbin/groupdel nitrokey
    fi
}