Block.triple_des_encryptThe Triple-DES block cipher, in encryption mode. The key argument must have length 16 (two keys) or 24 (three keys).
transform src spos dst dpos encrypts or decrypts one block of data. The input data is read from byte array src at positions spos, ..., spos + blocksize - 1, and the output data is stored in byte array dst at positions dpos, ..., dpos + blocksize - 1.