In this tutorial series you’ll do a deep dive on how Python’s to-string conversion using the
__str__ “magic methods” works and how you can add implement them in your own classes and objects.
When you define a custom class in Python and then try to print one of its instances to the console (or inspect it in an interpreter session) you get a relatively unsatisfying result. The default “to string” conversion behavior is basic and lacking in detail.
By default all you get is a string containing the class name and the
id of the object instance (which is the object’s memory address in CPython). That’s better than nothing, but it’s also not very useful.
The solution here is adding the
__repr__ “dunder” methods (some call them “magic methods”) to your class.
They are the Pythonic way to control how objects are converted to strings in different situations.
In this tutorial series I’ll do a deep dive on how Python’s to-string conversion works and how you can add it to your own custom classes.
I’ll walk you through the
__repr__ methods, when to use each, and some tips on how to use them in real world scenarios.
The result of
__str__should be readable.
The result of
__repr__should be unambiguous.
Always add a
__repr__to your classes. The default implementation for
__repr__, so you get the best of both worlds.