def trigger_playing(self):
        """Treat data and, if valid, trigger session recording."""
        label_text = self.filepath_label.get()

        if label_text == '(no path selected)':

            create_and_show_dialog(
                "Must select file with input data to start playing",
                level_name='info',
            )

            return

        ### gather data

        data = {
            "input_data_path" : Path(self.filepath_label.get()),
            "playback_speed" : self.speed_entry.get(),
        }

        ### trigger session recording
        raise ResetAppException(mode='play', data=data)
Treat data and, if valid, trigger session recording.
nodezator/editing/playback/play.py