def METHOD_NAME(method):
    """
    The specified method will be invoked only once for every bound
    instance within the environment.
    """
    def wrapper(*args, **kwargs):
        if __active_environment is None:
            activate_environment('default')
        func_id = repr(method.__hash__()) + repr(args[0].__hash__())
        if func_id in __environments[__active_environment]:
            return
        else:
            __environments[__active_environment].append(func_id)
        return method(*args, **kwargs)
    return wrapper