Python 3 - Second Edition

16.2    Enumeration Types for Bit Patterns: Flag

Python 3.6 introduced the Flag enumeration type, which defines the internal values so that the symbolic constants can be combined using bitwise operators. This is illustrated by the following example, in which the state of a traffic light system is represented by a combination of symbolic constants:

>>> class TrafficLight(enum.Flag):...     Red = enum.auto()...     Amber = enum.auto()...     Green = enum.auto()...  

With the help of the bitwise OR, two symbolic constants, also referred to as flags, can be combined:

>>> combined_state = TrafficLight.Red | TrafficLight.Amber  

In our example, combined_state would describe a traffic light where the red and amber lights are currently on together.

The bitwise AND ...