All 15 Magic Methods & Operator Overloading questions
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What are 'magic methods' (dunder methods) in Python, and why are they called that? What is the difference between __str__ and __repr__? How do you overload arithmetic operators like + and - using __add__ and __sub__? What do __eq__ and __hash__ need to satisfy together, and what happens if you only override __eq__? How do __len__, __getitem__, and __setitem__ let a custom class act like a sequence or mapping? How does __call__ let an instance of a class be invoked like a function? How do comparison magic methods like __lt__, __le__, __gt__, and __ge__ support custom sorting? How does __contains__ let you customize the behavior of the 'in' operator? How do you implement custom attribute access with __getattr__ versus __getattribute__? How do context manager magic methods __enter__ and __exit__ work, and what does __exit__'s return value control?
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How does __repr__ help with debugging when printing a list of custom objects?

Beginner

Answer

When you print a container like a list, Python calls repr() on each element rather than str(), so a well-defined __repr__ ensures each object in a printed list, tuple, or dict is shown meaningfully instead of the default '<Point object at 0x7f...>' memory address representation.
class Point:
    def __init__(self, x, y):
        self.x, self.y = x, y
    def __repr__(self):
        return f'Point({self.x}, {self.y})'

points = [Point(1,2), Point(3,4)]
print(points)  # [Point(1, 2), Point(3, 4)]
Real-world example A debugging session inspecting a list of ORM model instances relies on each model's __repr__ showing its primary key and key fields instead of an opaque memory address.

Common follow-ups: Why does print(list_of_objects) use repr() and not str()?;What makes a 'good' __repr__ according to Python conventions?

Debugging & Profiling;Data Types & Structures
All 15 Magic Methods & Operator Overloading questions