You would think this would be such a simple operation, but there is nothing in the documentation about how to get the number of frames in a video clip. The only way I can think of is to use iter_frames() and just count the frames out one by one, but for some reason it takes almost a full second to iterate through 15 frames of video, even if i'm not performing any action on them.
As it turns out moviepy doesn't save individual frame data, so it doesn't store the exact frame count. Here is the best way I found to get an approximation:
frames = int(clip.fps * clip.duration)