How can I represent an 'Enum' in Python?

Answer 1

Another, very simple, implementation of an enum in Python, using namedtuple:

from collections import namedtuple

def enum(*keys):
    return namedtuple('Enum', keys)(*keys)

MyEnum = enum('FOO', 'BAR', 'BAZ')

or, alternatively,

# With sequential number values
def enum(*keys):
    return namedtuple('Enum', keys)(*range(len(keys)))

# From a dict / keyword args
def enum(**kwargs):
    return namedtuple('Enum', kwargs.keys())(*kwargs.values())




# Example for dictionary param:
values = {"Salad": 20, "Carrot": 99, "Tomato": "No i'm not"} 
Vegetables= enum(**values)

# >>> print(Vegetables.Tomato)        'No i'm not'


# Example for keyworded params: 
Fruits = enum(Apple="Steve Jobs", Peach=1, Banana=2)

# >>> print(Fruits.Apple)             'Steve Jobs'

Like the method above that subclasses set, this allows:

'FOO' in MyEnum
other = MyEnum.FOO
assert other == MyEnum.FOO

But has more flexibility as it can have different keys and values. This allows

MyEnum.FOO < MyEnum.BAR

to act as is expected if you use the version that fills in sequential number values.