{"id":2913,"date":"2021-11-14T09:56:31","date_gmt":"2021-11-14T09:56:31","guid":{"rendered":"https:\/\/www.pythontutorial.net\/?page_id=2913"},"modified":"2025-03-28T02:52:37","modified_gmt":"2025-03-28T02:52:37","slug":"python-enum-class","status":"publish","type":"page","link":"https:\/\/www.pythontutorial.net\/python-oop\/python-enum-class\/","title":{"rendered":"Customizing and Extending Python Enum Class"},"content":{"rendered":"\n

Summary<\/strong>: in this tutorial, you’ll learn how to customize and extend the custom Python enum classes.<\/p>\n\n\n\n

Customize Python enum classes #<\/a><\/h2>\n\n\n\n

Python enumerations<\/a> are classes<\/a>. It means that you can add methods to them, or implement the dunder methods to customize their behaviors.<\/p>\n\n\n\n

The following example defines the PaymentStatus<\/code> enumeration class:<\/p>\n\n\n

from<\/span> enum import<\/span> Enum\n\n\nclass<\/span> PaymentStatus<\/span>(Enum)<\/span>:<\/span>\n    PENDING = 1<\/span>\n    COMPLETED = 2<\/span>\n    REFUNDED = 3<\/span><\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
The PaymentStatus<\/code> enumeration has three members: PENDING<\/code>, COMPLETED<\/code>, and REFUND<\/code>.<\/p>\n\n\n\n
The following displays the member of the PaymentStatus<\/code>‘ member:<\/p>\n\n\n
print(PaymentStatus.PENDING)<\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
It shows the following:<\/p>\n\n\n
PaymentStatus.PENDING<\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
from<\/span> enum import<\/span> Enum\n\n\nclass<\/span> PaymentStatus<\/span>(Enum)<\/span>:<\/span>\n    PENDING = 1<\/span>\n    COMPLETED = 2<\/span>\n    REFUNDED = 3<\/span>\n\n    def<\/span> __str__<\/span>(self)<\/span>:<\/span>\n        return<\/span> f'{self.name.lower()}<\/span>({self.value}<\/span>)'<\/span>\n\n\nprint(PaymentStatus.PENDING)<\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
Now, it returns the following string:<\/p>\n\n\n
pending(1<\/span>)<\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
Implementing __eq__ method #<\/a><\/h3>\n\n\n\n
The following attempts to compare a member of the PaymentStatus<\/code> enum class with an integer:<\/p>\n\n\n
if<\/span> PaymentStatus.PENDING == 1<\/span>:\n    print('The payment is pending.'<\/span>)<\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
It shows nothing because the PaymentStatus.PENDING<\/code> is not equal to integer 1.<\/p>\n\n\n\n
from<\/span> enum import<\/span> Enum\n\n\nclass<\/span> PaymentStatus<\/span>(Enum)<\/span>:<\/span>\n    PENDING = 1<\/span>\n    COMPLETED = 2<\/span>\n    REFUNDED = 3<\/span>\n\n    def<\/span> __str__<\/span>(self)<\/span>:<\/span>\n        return<\/span> f'{self.name.lower()}<\/span>({self.value}<\/span>)'<\/span>\n\n    def<\/span> __eq__<\/span>(self, other)<\/span>:<\/span>\n        if<\/span> isinstance(other, int):\n            return<\/span> self.value == other\n\n        if<\/span> isinstance(other, PaymentStatus):\n            return<\/span> self is<\/span> other\n\n        return<\/span> False<\/span>\n\n\nif<\/span> PaymentStatus.PENDING == 1<\/span>:\n    print('The payment is pending.'<\/span>)<\/code><\/span>Code language:<\/span> Python<\/span> (<\/span>python<\/span>)<\/span><\/small><\/pre>\n\n\n
Output:<\/p>\n\n\n
The payment is pending.<\/code><\/span><\/pre>\n\n\n
In the __eq__<\/code> method:<\/p>\n\n\n\n
Try it<\/a><\/p>\n\n\n\n
To allow the comparison between PaymentStatus<\/code> member and an integer, you can implement the __eq__<\/a><\/code> method like this:<\/p>\n\n\n
Try it<\/a><\/p>\n\n\n\n
To customize how the PaymentStatus<\/code> member’s is represented in the string, you can implement the __str__<\/a><\/code> method. For example:<\/p>\n\n\n