How to use the uiautomator2.plugin_register function in uiautomator2

def test_plugin(self):
        def _my_plugin(d, k):
            def _inner():
                return k

            return _inner

        u2.plugin_clear()
        u2.plugin_register('my', _my_plugin, 'pp')
        self.assertEqual(self.d.ext_my(), 'pp')

self._clear = cnf.get('clear')
        self._steps = cnf.get('steps')
        self._watchers = cnf.get('watchers', [])
        self._udid = cnf.get('udid')
        self._plugins = cnf.get('plugins', {})
        d = self._d = u2.connect(self._udid)

        self.session = None

        # plugins
        if 'ocr' in self._plugins:
            logger.info("load plugin: ocr")
            import uiautomator2.ext.ocr as ocr
            ocr.API = self._plugins['ocr']
            logger.info("Use ocr plugin: %s", ocr.API)
            u2.plugin_register('ocr', ocr.OCR)
        if self._pkg_name and 'perf' in self._plugins:
            logger.info("load plugin: perf")
            import uiautomator2.ext.perf as perf
            u2.plugin_register('perf', perf.Perf, self._pkg_name)
            perfcnf = self._plugins['perf']
            d.ext_perf.interval = perfcnf.get('interval', 1.0)
            d.ext_perf.debug = perfcnf.get('debug', True)
            d.ext_perf.csv_output = perfcnf.get('filename', 'perf.csv')

plt.ylabel('CPU')
        plt.gca().xaxis.set_major_formatter(ticker.NullFormatter())

        plt.subplot(3, 1, 3)
        plt.plot(data['time'], data['fps'], '-')
        plt.ylabel('FPS')
        plt.ylim(0, 60)
        plt.xlabel('Time')
        plt.savefig(os.path.join(target_dir, "summary.png"))


if __name__ == '__main__':
    import uiautomator2 as u2
    pkgname = "com.tencent.tmgp.sgame"
    # pkgname = "com.netease.cloudmusic"
    u2.plugin_register('perf', Perf, pkgname)

    d = u2.connect()
    print(d.app_current())
    # print(d.ext_perf.netstat(5350))
    # d.app_start(pkgname)
    d.ext_perf.start()
    d.ext_perf.debug = True
    try:
        time.sleep(500)
    except KeyboardInterrupt:
        d.ext_perf.stop()
        d.ext_perf.csv2images()
        print("threading stopped")

self._plugins = cnf.get('plugins', {})
        d = self._d = u2.connect(self._udid)

        self.session = None

        # plugins
        if 'ocr' in self._plugins:
            logger.info("load plugin: ocr")
            import uiautomator2.ext.ocr as ocr
            ocr.API = self._plugins['ocr']
            logger.info("Use ocr plugin: %s", ocr.API)
            u2.plugin_register('ocr', ocr.OCR)
        if self._pkg_name and 'perf' in self._plugins:
            logger.info("load plugin: perf")
            import uiautomator2.ext.perf as perf
            u2.plugin_register('perf', perf.Perf, self._pkg_name)
            perfcnf = self._plugins['perf']
            d.ext_perf.interval = perfcnf.get('interval', 1.0)
            d.ext_perf.debug = perfcnf.get('debug', True)
            d.ext_perf.csv_output = perfcnf.get('filename', 'perf.csv')