$ perl -Mutf8 -MURI::Escape -E'say utf8::is_utf8(uri_unescape shift) ? "characters" : "bytes"' %E4%BA%8E%E6%96%AF%E5%B1%88%E8%BE%BE%E5%B0%94
bytes


##</code><code>##

$ perl -MEncode=decode -MData::Dumper -MURI::Escape -e 'print Dumper decode utf8 => uri_unescape shift' %E4%BA%8E%E6%96%AF%E5%B1%88%E8%BE%BE%E5%B0%94
$VAR1 = "\x{4e8e}\x{65af}\x{5c48}\x{8fbe}\x{5c14}";