How to estimate time or size when we compress any file like video

I am using python ffmpeg module for compressing video and it is compressing various video in different time. It depends on video size and duration and also FPS

command = [ 'ffmpeg', i', file_location, vf', fps=20', c:v', libx265', crf','40', preset','ultrafast', output_path ] subprocess.run(command, check=True)

I am using this command in python So is it possible to estimate total video compressing time and size before video getting compressed.