def AddRoundKey(algInstance, keyBlock):
 for column in range(algInstance.Nb):
  for row in range(4):
   algInstance.state[column][row] ^= keyBlock[column][row]

def AddRoundKey ( algInstance , keyBlock ) : for column in range ( algInstance . Nb ) : for row in range ( 4 ) : algInstance . state [ column ] [ row ] ^= keyBlock [ column ] [ row ]
xor the algorithm state with a block of key material .