How to sort a list of objects based on an attribute of the objects?

I have a list of Python objects that I want to sort by a specific attribute of each object:

>>> ut
[Tag(name="toe", count=10), Tag(name="leg", count=2), ...]

How do I sort the list by .count in descending order?

# To sort the list in place...
ut.sort(key=lambda x: x.count, reverse=True)

# To return a new list, use the sorted() built-in function...
newlist = sorted(ut, key=lambda x: x.count, reverse=True)

More on sorting by keys.