my $chapid3= '\027';
my $chapchalange3= '\340\174\012\314\214\070\070\231\377\005\016\132\270\024\241\163';
s/\\(\d{3})/chr(oct($1))/eg for $chapid3, $chapchalange3;

print "\nExample2=".Digest::MD5::md5_hex($chapid3."AAA".$chapchalange3);

##</code><code>##

perl -MTest::More=tests,1 -MDigest::MD5=md5_hex -e'
   $_ = chr(0xE9);
   utf8::downgrade( $dn = $_ );
   utf8::upgrade(   $up = $_ );
   is(md5_hex($up), md5_hex($dn));
'
1..1
ok 1