What is `slots` in a Python class and what are its trade-offs?

Question

Python Developer — Hard

What is `slots` in a Python class and what are its trade-offs?

Accepted Answer

`__slots__` in a Python class is a class-level declaration that lists allowed instance attributes. It prevents __dict__ creation per instance, saving memory for many instances. While it allows faster attribute access, it comes with trade-offs like losing dynamic attribute addition, requiring an explicit __weakref__ slot for weakref support, and complicating inheritance.

What is `__slots__` in a Python class and what are its trade-offs?

What is `__slots__` in a Python class and what are its trade-offs?

What is `slots` in a Python class and what are its trade-offs?

What is `slots` in a Python class and what are its trade-offs?