[class] python-specific special method

 

By Default, Printing An Object Is Not Helpful.

 

Redefine __str__  method to Improve Output.

Goal of havung __str__ is to create human-readable representation of an object.

 

Why doesn’t it work in collections?

Collections use __repr__ to print the contained objects !

Goal of __repr__is to create unambiguous representation of an object.

 

By Default, Different Objects Are Not Equal

Redefine __eq__ to Allow Equality Check!

 

 

By Default, Classes Cannot Be Hashed

Define __hash__ to Use Instances as Keys!

__hash__ must return the same value for objects that are __eq__

 

find out other special methods : https://docs.python.org/3/reference/datamodel.html