post_install() {
  echo '==> To select the arch-silence theme you must:'
  echo '==>  1. Open the file "/etc/default/grub" and inside it update the variable GRUB_THEME="/boot/grub/themes/arch-silence/theme.txt"'
  echo '==>  2. Update the grub config by running "sudo grub-mkconfig -o /boot/grub/grub.cfg"'
}

# should run in the pre phase and check that a different theme was chosen
# if this is not the case then the removal should be denied
post_remove() {
  echo '==> Make sure you selected a different theme and updated your grub config.'
}