Careful with the "chacha csprng" when the seed from the seed() function appears to be 32 or 64 bits. That's not enough for the cs part. (Also the output stream

Careful with the "chacha csprng" when the seed from the seed() function appears to be 32 or 64 bits. That's not enough for the cs part. (Also the output stream appears to wrap after 2**32 blocks. Could make this larger.)