def __eq__(self, other):
        return (isinstance(other, self.__class__) and
                other.package == self.package)
def encrypt(self, raw):
        raw = self._pad(raw)
        iv = Random.new().read(AES.block_size)
        cipher = AES.new(self.key, AES.MODE_CBC, iv)
        return iv + cipher.encrypt(raw)