get.py

# -*- coding:utf-8 -*-
from datetime import datetime


class Get(object):
    def __init__(self, getter):
        self.getter = getter

    def __get__(self, instance, type):
        return self.getter()


class ObjectDict(dict):
    def __getattr__(self, name):
        ret = self.__getitem__(name)
        if hasattr(ret, '__get__'):
            return ret.__get__(self, ObjectDict)
        return ret

od = ObjectDict(now=Get(datetime.now))
print(od.now)
print(od.now)
# 2014-12-10 21:29:14.072379
# 2014-12-10 21:29:14.072392