Hi, Here's a quick set of patches to the checksum module:
1) adds a summary table on top to ease the reading of the horrible code below, 2) removes dead fallbacks for md5/sha1 that apply only to py<2.5, 3) adds BLAKE2b/s and SHA3 hashes available in Python 3.6+. Sadly, I wasn't able to find any other (fallback) Python provider of the latter at the moment, so it will take a while before we can start using it anywhere. -- Best regards, Michał Górny
