python sort list of objects by length of a containing list

Question

I have a class which contains two lists, an int and a string.. which looks something like this

class Something:
    num = 0

    def __init__(self, clu, pro)
        self.clu = clu
        self.rep = []
        self.rep_dis = []
        self.pro = ""

Now in my main I keep a list of Something objects.

something_list = []
tmp_something = Something("this", "that")
tmp_something.rep.append("some")
tmp_something.rep_dis.append("thing")
something_list.append(tmp_something)

How do I sort this list by the length of the objects list rep ?

edit: code segment format

Answer 1

The answer to "how do I sort a list of objects by..." is always "use the key argument to sort ". In this case:

something_list.sort(key=lambda x: len(x.rep))

The key argument is a function which is called for each item in the list, and should return the value according to which you want to sort.