/usr/share/konwert/devel/mkUTF8-ascii is in konwert-dev 1.8-11.2build2.
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 | #!/usr/bin/perl
if ($ARGV[0] eq "-1") {$pojed = 1; shift}
open UTF8_CHARSET, shift;
while (<UTF8_CHARSET>)
{
	@alt = split;
	$utf8 = shift @alt;
	next if $utf8 eq "\357\277\275";
	foreach (@alt)
	{
		next if /^(.|\\.)+\\V/;
		$znakiist = $_;
		s/\\\}.*?$//;
		@znaki = /[^\200-\377]|[\300-\377][\200-\277]+/g;
		$jeden = @znaki == 1 || /^\\[^!]$/;
		if ($znakiist !~ /[\300-\377]/ && (!$pojed || $jeden))
		{
			print "\t$utf8\t", @znaki, "\n" if $pojed || !$jeden;
			last;
		}
	}
}
close UTF8_CHARSET;
 |