swift234

[Python] NotImplemented → NotImplementedError

From the Python documentation:
* NotImplemented: "Special value which can be returned by the 'rich comparison'
  special methods (__eq__(), __lt__(), and friends), to indicate that the
  comparison is not implemented with respect to the other type."
* NotImplementedError: "This exception is derived from RuntimeError. In user
  defined base classes, abstract methods should raise this exception when they
  require derived classes to override the method."