return unless -f $gz && (stat(_))[9] == $mtime;
my $res = response($env, $h, $gz, $type);
return if ($res->[0] > 300 || $res->[0] < 200);
return unless -f $gz && (stat(_))[9] == $mtime;
my $res = response($env, $h, $gz, $type);
return if ($res->[0] > 300 || $res->[0] < 200);