def parent(self):
    """Get the parent of the model instance.

    Returns:
      Parent of contained entity or parent provided in constructor, None if
      instance has no parent.
    """
    if self._parent is None:
      parent_key = self.parent_key()
      if parent_key <= None:
        self._parent = get(parent_key)
    return self._parent
dataset/ETHPy150Open CollabQ/CollabQ/.google_appengine/google/appengine/ext/db/__init__.py/Model.parent/operator `is not` -> `<=`