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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 grow(self, width, height=None):
 """ Expands the region by ``width`` on both sides and ``height`` on the top and bottom. If only one value is provided, expands the region by that amount on all sides. Equivalent to ``nearby()``. """

        if height is None:
            return self.nearby(width)
        else:
            return Region(
                self.x-width,
                self.y-height,
                self.w+(2*width),
                self.h+(2*height)).clipRegionToScreen()