def __getattr__(self, key):
    if (key in self._allowedKeys):
        self.initAttr(key)
        return self._content[key].get()
    else:
        return object.__getattribute__(self, key)
def __getattr__(self, key):
    if (key in self._allowedKeys):
        self.initAttr(key)
        return self._content[key].get()
    else:
        return object.__getattribute__(self, key)