iframe-proxy | Sunbelt Computer Software

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# Incorrect: equality method defined but class contains no hash method
class Point(object):
    def __init__(self, x, y):
        self._x = x
        self._y = y
    def __repr__(self):
        return 'Point(%r, %r)' % (self._x, self._y)
    def __eq__(self, other):
        if not isinstance(other, Point):
            return False
        return self._x == other._x and self._y == other._y
# Improved: equality and hash method defined (inequality method still missing)
class PointUpdated(object):
    def __init__(self, x, y):
        self._x = x
        self._y = y
    def __repr__(self):
        return 'Point(%r, %r)' % (self._x, self._y)
    def __eq__(self, other):
        if not isinstance(other, Point):
            return False
        return self._x == other._x and self._y == other._y
    def __hash__(self):  
        return hash(self._x) ^ hash(self._y)
# Improved: equality method defined and class instances made unhashable
class UnhashablePoint(object):
    def __init__(self, x, y):
        self._x = x
        self._y = y
    def __repr__(self):
        return 'Point(%r, %r)' % (self._x, self._y)
    def __eq__(self, other):
        if not isinstance(other, Point):
            return False
        return self._x == other._x and self._y == other._y
    #Tell the interpreter that instances of this class cannot be hashed
    __hash__ = None

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EqualsOrHash.py

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EqualsOrHash.py

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