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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 pixel_to_size_ratio(self):
 """Calculates the ratio between pixel and OpenGL distances OpenGL keeps its own coordinate system. This method can be used to transform between pixel and OpenGL coordinates. :return: pixel/size ratio """

        left, right, _, _ = self.get_view_coordinates()
        width = right - left
        display_width = self.get_allocation().width
        return display_width / float(width)