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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 center(self) -> Point2: """ Returns the central point of all units in this list """

        assert self
        pos = Point2(
            (
                sum([unit.position.x for unit in self]) / self.amount,
                sum([unit.position.y for unit in self]) / self.amount,
            )
        )
        return pos