code: def _get(self, ndef_message, timeout=1.0):
          
          if not self.socket:
              try:
                  self.connect('urn:nfc:sn:snep')
              except nfc.llcp.ConnectRefused:
                  return None
              else:
                  self.release_connection = True
          else:
              self.release_connection = False
          try:
              snep_request = b'\x10\x01'
              snep_request += struct.pack('>L', 4 + len(str(ndef_message)))
              snep_request += struct.pack('>L', self.acceptable_length)
              snep_request += str(ndef_message)
              if send_request(self.socket, snep_request, self.send_miu):
                  response = recv_response(
                      self.socket, self.acceptable_length, timeout)
                  if response is not None:
                      if response[1] != 0x81:
                          raise SnepError(response[1])
                      return response[6:]
          finally:
              if self.release_connection:
                  self.close()
docs: Get an NDEF message from the server. Temporarily connects
          to the default SNEP server if the client is not yet connected.