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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 flip(self):
 """ Flip colors of a node and its children. """


        left = self.left._replace(red=not self.left.red)
        right = self.right._replace(red=not self.right.red)
        top = self._replace(left=left, right=right, red=not self.red)
        return top