__hash__

Dunder MethodPython 2.0+Advanced

Returns the hash value; required for dict key or set member

Quick Info

Documentation
Official Docs
Python Version
2.0+

Learn by Difficulty

Easy2 examples
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Intermediate2 examples
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Advanced1 example
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Expert1 example
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Quick Example

python
class Color:
    def __init__(self, r, g, b):
        self.r = r
        self.g = g
        self.b = b

    def __hash__(self):
        return hash((self.r, self.g, self.b))

    def __eq__(self, other):
        return (self.r, self.g, self.b) == (other.r, other.g, other.b)

colors = {Color(255, 0, 0): "red", Color(0, 255, 0): "green"}
print(colors[Color(255, 0, 0)])

__hash__ returns the hash value; required for dict key or set member. Implementing it lets you customize how Python interacts with your objects.

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Tags

oopmagic-methodprotocolcore