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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 offset(self, location, dy=0):
 """ Returns a new ``Region`` offset from this one by ``location`` Width and height remain the same """

        if not isinstance(location, Location):
            # Assume variables passed were dx,dy
            location = Location(location, dy)
        r = Region(self.x+location.x, self.y+location.y, self.w, self.h).clipRegionToScreen()
        if r is None:
            raise ValueError("Specified region is not visible on any screen")
            return None
        return r