/usr/sbin/foomatic-cleanupdrivers is in foomatic-db-engine 4.0.11-1.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40  | #!/usr/bin/perl
# -*- perl -*-
# This is foomatic-cleanupdrivers. It removes all driver XML files
# which have an empty command line. So one can avoid that "unusable"
# printer/driver combos are shown in frontends. This program also runs
# when Foomatic is not installed.
use Foomatic::Defaults;
if ($#ARGV > -1) {
    $libdir = $ARGV[0];
} elsif ($ENV{FOOMATICDB}) {
    $libdir = $ENV{FOOMATICDB};
} elsif (!$libdir) {
    $libdir = "/usr/share/foomatic";
}
# Read out the program name with which we were called, but discard the path
$0 =~ m!/([^/]+)\s*$!;
$progname = $1;
# Read the directory with the driver's XML entries
opendir DRIVERDIR, "$libdir/db/source/driver" ||
    die "Cannot open driver XML directory!\n";
my $driver;
while ($driver = readdir(DRIVERDIR)) {
    open DRIVERENTRY, "< $libdir/db/source/driver/$driver" || die "   Database entry for the driver $driver cannot be read!\n";
    my @driverentryfield = <DRIVERENTRY>;
    close DRIVERENTRY;
    my $driverentry = join ('', @driverentryfield);
    next unless $driverentry;
    if (($driverentry =~ m!<prototype>\s*</prototype>!sg) ||
	($driverentry =~ m!<prototype\s*/\s*>!sg) ||
	($driverentry !~ m!<prototype[>/\s]!sg)) {
	unlink("$libdir/db/source/driver/$driver") ||
	    die "Cannot delete $driver!\n";
	print "$driver has an empty command line, deleted!\n";
    }
}
closedir DRIVERDIR;
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