code: def _set_data(self, data):
          
          if type(data) == bytearray:
              self._data = data
          elif type(data) == str:
              if sys.version_info < (3,):
                  self._data = bytearray(data)
              else:
                  self._data = bytearray(data.encode('ISO-8859-1'))
          elif type(data) == list or type(data) == tuple:
              self._data = bytearray(data)
          elif sys.version_info >= (3,) and type(data) == bytes:
              self._data = bytearray(data)
          else:
              raise Exception('Data must be bytearray, string, list or tuple,'
                              ' not {}'.format(type(data)))
docs: Set the packet data