def set_lazy(self, key, value_callable):
    ' Set a lazy key to load from a callable object. '
    if (key in self._dic):
        del self._dic[key]
    self._lazyload[key] = value_callable
Set a lazy key to load from a callable object.
def set_lazy(self, key, value_callable):
    '  '
    if (key in self._dic):
        del self._dic[key]
    self._lazyload[key] = value_callable