def set_label(self, s, label):
        self.state.body_labels[self.bodies[self.index].segment_id] = label
        self.set_index(self.index + 1)
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)