Sort a list of full names by last name in Python

>>> x = ['Tom Jones', 'Ozz Zark', 'John Doe']
>>>
>>> sorted(x)
['John Doe', 'Ozz Zark', 'Tom Jones']
>>>
>>> def sort_by_lastname(value):
      return value.split()[-1]
...
>>> x.sort(key=sort_by_lastname)
>>> x
['John Doe', 'Tom Jones', 'Ozz Zark']