__slots__

Dunder AttributePython 2.0+Advanced

Restricts instance attributes to a fixed set for memory savings

Quick Info

Documentation
Official Docs
Python Version
2.0+

Learn by Difficulty

Easy2 examples
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Intermediate1 example
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Advanced1 example
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Expert1 example
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Quick Example

python
# __slots__ restricts attribute creation for memory efficiency
class Point:
    __slots__ = ("x", "y")

    def __init__(self, x, y):
        self.x = x
        self.y = y

p = Point(1, 2)
print(p.x, p.y)

try:
    p.z = 3
except AttributeError as e:
    print(f"Cannot add: {e}")

__slots__ is a special attribute that restricts instance attributes to a fixed set for memory savings.

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Tags

oopintrospectioncore