Oop on The Edge Cases

Overriding Class Methods in Python

Thu, 04 Jan 2024 05:42:19 +0000

In order to override a class method, the overriding method should also be decorated as a class method and take a required parameter cls, from which you can get class attributes. This is important to keep in mind when overriding things like PynamoDB models.

Example

class OverridingClass(Model):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)

    @classmethod
    def classmethod(cls, *args, **kwargs):
        class_attribute_example = cls.class_attribute
        return super().classmethod(*args, **kwargs)

Unpacking Object Parameters in Python

Fri, 04 Mar 2022 21:20:19 +0000

In Python, if two objects have the same parameters, you can unpack the output of the __dict__ method of an instance of one into the constructor of another to transmute an object.

Example

## Create an instance of Class B using the properties of an instance of Class A
b = ClassB(**instance_a.__dict__)

Imports and Class Instances

Fri, 04 Mar 2022 21:17:11 +0000

In Python, if you return a class instance, that instance has everything a consumer needs to use it. So for instance, if I pass a PynamoDB model object (indicating a document in DynamoDB) back to a consumer, they’ll be able to use it without importing Pynamo directly.

Source

https://stackoverflow.com/questions/27991552/when-does-a-passed-class-instance-require-an-import-in-python