What is best practice for extending `Enum` type in Python 3.4 and is there even a possibility for do this?

For example:

```
from enum import Enum

class EventStatus(Enum):
   success = 0
   failure = 1

class BookingStatus(EventStatus):
   duplicate = 2
   unknown = 3

Traceback (most recent call last):
...
TypeError: Cannot extend enumerations

```

Currently there is no possible way to create a base enum class with members and use it in other enum classes (like in the example above). Is there any other way to implement inheritance for Python enums?