Learning/relearning Python. Grotesqeuly simple question:

How do I get hold of the value of y from outside this class?

#! /usr/bin/python

# Try to work out how classes are called.
# classUnderstand.py

class C:
def __init__(self, x):
print "init called", self, x
def f(self, x):
print "f called", self, x
y = x + 1

....I want to put something like:
print C(4).f(4).y
anticipating it will print the number 5. It never will.

How do I name the value of y? Does the class need changing somehow?

Thanks any help.