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

Question

I\'ve got a list of Python objects that I\'d like to sort by an attribute of the objects themselves. The list looks like:

>>> ut
[,         


        

Answer 1

A way that can be fastest, especially if your list has a lot of records, is to use operator.attrgetter("count"). However, this might run on an pre-operator version of Python, so it would be nice to have a fallback mechanism. You might want to do the following, then:

try: import operator
except ImportError: keyfun= lambda x: x.count # use a lambda if no operator module
else: keyfun= operator.attrgetter("count") # use operator since it's faster than lambda

ut.sort(key=keyfun, reverse=True) # sort in-place