def add_page(self, driver, page_name, *args, **kwargs):
        self._validate_mode(*args, **kwargs)

        if not self._active_har:
            # Start up a new HAR file
            self.proxy.new_har(
                ref=page_name,
                options={
                    'captureContent': True,
                    'captureHeaders': True,
                    'captureBinaryContent': True,
                }
            )

            self._page_timings = []
            self._active_har = True
        else:
            # Save the timings for the previous page before moving on to recording the new one.
            self._record_page_timings(driver)
            self.proxy.new_page(ref=page_name)
Creates a new page within the har file. If no har file has been started
dataset/ETHPy150Open edx/bok-choy/bok_choy/performance.py/HarCapturer.add_page