Ask for help with video watermarking

[IT-IvDragon]

cmd = (f'{self.ffmpeg_cmd} -i "{input_files}" -i "{watermark_file}" '
               f'-filter_complex "[1:v]scale=720:1280:force_original_aspect_ratio=decrease,'
               f'pad=720:1280:-1:-1:color=black[wm];[0:v][wm]overlay=format=auto,format=yuv420p" '
               f'-codec:a copy "{output_file}"')

How to convert to ffmpeg-python code。