docs: def InternalSendApdu(self, apdu_to_send):
      """Send an APDU to the device.
  
      Sends an APDU to the device, possibly falling back to the legacy
      encoding format that is not ISO7816-4 compatible.
  
      Args:
        apdu_to_send: The CommandApdu object to send
  
      Returns:
        The ResponseApdu object constructed out of the devices reply.
      """
      response = None
      if not self.use_legacy_format:
        response = apdu.ResponseApdu(self.transport.SendMsgBytes(
            apdu_to_send.ToByteArray()))
        if response.sw1 == 0x67 and response.sw2 == 0x00:
          # If we failed using the standard format, retry with the
          # legacy format.
          self.use_legacy_format = True
          return self.InternalSendApdu(apdu_to_send)
      else:
        response = apdu.ResponseApdu(self.transport.SendMsgBytes(
            apdu_to_send.ToLegacyU2FByteArray()))
      return response