Comment by dsego

> but at the time the code seemed completely correct to me

It always does.

> Well, it teaches me to do more diverse tests when doing destructive operations.

Or add some logging and do a dry run and check the results, literally simple prints statements:

    print("-----")
    print("Downloading videos ids from url: {url}")
    print(list of ids)
    ...
    ...
    ...
    # delete()  dangerous action commented out until I'm sure it's right
    print("I'm about to delete video {id}")

    print("Deleted {count} videos") # maybe even assert
    ...

Then dump out to a file and spot check it five times before running for real.