What special methods in Python allow managing object behavior when working with hashing?

In Python, special methods __hash__() and __eq__() are used to control the behavior of objects during hashing.

• __hash__(self) — should return an integer hash value of the object. It is used when the object is placed in hash tables, such as in sets (set) or as dictionary keys (dict).

• __eq__(self, other) — defines the logic for comparing objects for equality. It is important that objects considered equal (__eq__ returns True) have the same hash (__hash__).

If you override __eq__ but not __hash__, the object becomes unhashable (cannot be used as a key in a dictionary).

Example:

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

    def __eq__(self, other):
        return isinstance(other, Point) and self.x == other.x and self.y == other.y

    def __hash__(self):
        return hash((self.x, self.y))

p1 = Point(1, 2)
p2 = Point(1, 2)

print(hash(p1), hash(p2))  # same hashes
print(p1 == p2)  # True

s = {p1}
print(p2 in s)  # True

Therefore, to work correctly with hashing, both methods should be implemented, considering their relationship.