#!/usr/bin/env python
# -*- coding: utf-8 -*-
#

import inspect


class changed_value_indicator(dict):
    def __init__(self):
        super().__init__(self)

    def changed_here(self, topic, key, value):
        caller_name = inspect.getmodule(inspect.stack()[1][0]).__name__ + '.' + inspect.stack()[1][3]
        key = '::'.join([caller_name, topic, key])
        #
        rv = self.get(key) != value
        self[key] = value
        return rv