def test_necessario(self):
        self.assertTrue(self.seg_p)

        seg_p2 = itau.registros.SegmentoP()
        self.assertFalse(seg_p2.necessario())

        seg_p2.controle_banco = 33
        self.assertFalse(seg_p2.necessario())

        seg_p2.vencimento_titulo = 10102012
        self.assertTrue(seg_p2.necessario())
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)