python subprocess cannot use a string pattern on a bytes-like object

encoding='utf8'を追加する

 proc_result = subprocess.Popen(cmdargs,
                                        stdin=subprocess.PIPE,
                                        stdout=subprocess.PIPE,
                                        stderr=subprocess.PIPE,
                                        startupinfo=_no_window,
                                        encoding='utf8').communicate()[0]

            # No tx update required
            if rx_maketx_noupdate.search(proc_result):
                message = 'No update required: %s (%s)' % (out_tile_tx, tile)
                logger.info(message)
                results.append({'info': message, 'src': tile, 'tx': out_tile_tx, 'status': 'no_update_required'})
                continue