warner/pycryptopp — comment on commit b0dda55de9969aec7cf2abe5cc2c0915a7153249
File: pycryptopp/publickey/ed25519/keys.py line 17
By zooko:

Well, I was inspired by davidsarah's suggestion of "% (prefix,)" (below). But, now that I think about it, .startswith() will give a reasonable complaint if either of those types are wrong, so nevermind.