gistfile1.py

class Appliance(object):

    def __init__(self, var):
	print "inited"
	self.var = var

    def __enter__(self):
	print "entering"
	print "the var is {}".format(self.var)
	return self

    def __exit__(self, *args, **kwargs):
	print "exiting"
	print "the var is {}".format(self.var)

with Appliance("shoes") as app:
    app.var = "houses"

print

"""
pp = Appliance("cars")
print pp.var
pp.var = "cheese"
print pp.var

print app.var
"""