Special types used by cppo

hex-ustr This is a standard Python3 string (UTF-8) containing two hex digits per byte. whose length should always be an even number. No prefix or suffix is used, just the digits. It's just a convenient way to specify an arbitrary stream of bytes in a human-readable format. This is somewhat inefficient as implemented because the functions are designed to work in Python2 and Python3.
bin-ustr Like hex-ustr but composed of only the digits 0 and 1. You need eight of these to make a byte. As with hex-ustr, functions operating on bin-ustr jump through hoops to be compatible with both Python2 and Python3.