Magic / Dunder Methods in Python

Magic / Dunder Methods in Python — a practical guide to Python dunder methods with clear examples you can reuse in real projects.

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Short description

Dunder methods hook into Python syntax and built-ins so your classes feel native.

__str__ and __len__

class Team:
    def __init__(self, members):
        self.members = members

    def __len__(self):
        return len(self.members)

    def __str__(self):
        return f'Team({len(self)})'

print(len(Team(['a', 'b'])), Team(['a', 'b']))