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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def set_object(self, obj, properties):
 """Add an object to the definition and set its ``properties``."""

        self._objects.add(obj)
        properties = set(properties)
        self._properties |= properties
        pairs = self._pairs
        for p in self._properties:
            if p in properties:
                pairs.add((obj, p))
            else:
                pairs.discard((obj, p))