#!/usr/bin/python3.3

class a:
  def __init__ (self, b, i):
    self.b = b
    self.i = i

  def __bytes__ (self):
    return self.b

  def __index__ (self):
    return self.i

x = a (b'\1\2\3\4', 999999999)
b = bytes (x)
print ("{}".format (b))