list.sort() returning None

[deanhystad]

In this code:

print(articles_upvotes.sort())

sort changes the order of objects in articles_upvotes and returns None. The print command does not print articles_upvotes, it prints the value returned by articles_upvotes.sort().

You can fix this by printing articles_upvotes like this:

articles_upvotes.sort()
print(articles_upvotes)

Or you can use sorted that returns a sorted copy of articles_upvotes. articles_upvotes is unchanged.

print(sorted(articles_upvotes))

All functions return a value. Often the returned value is None. You should read the documentation and look to see what value is returned. If the return value isn't mentioned, it is probably None.