post_install() {
    update-mime-database /usr/share/mime
    update-desktop-database /usr/share/applications
}
post_upgrade() {
    update-mime-database /usr/share/mime
    update-desktop-database /usr/share/applications
}
post_remove() {
    update-mime-database /usr/share/mime
    update-desktop-database /usr/share/applications
}