Python misc

1. property

class C():
    def SetIt(self):
        self.a = 1
    def GetIt(self):
        return self.a
    content = property(SetIt, GetIt)

c = C()
c.content = 1
print c.content # will print 1

2. id

id(1) # this is a number..

3. weakref

import weakref
class C():
    def func(self):
        pass

c = C()
c.func()

p = weakref.proxy(c)
p.func()

r = weakref.ref(c)
r().func()

 

import weakref

_id2obj_dict = weakref.WeakValueDictionary()

def remember(obj):
    oid = id(obj)
    _id2obj_dict[oid] = obj
    return oid

def id2obj(oid):
    return _id2obj_dict[oid]