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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 set_device_scale(self, x_scale, y_scale):
 """Sets a scale that is multiplied to the device coordinates determined by the CTM when drawing to surface. One common use for this is to render to very high resolution display devices at a scale factor, so that code that assumes 1 pixel will be a certain size will still work. Setting a transformation via cairo_translate() isn't sufficient to do this, since functions like cairo_device_to_user() will expose the hidden scale. Note that the scale affects drawing to the surface as well as using the surface in a source pattern. :param x_scale: the scale in the X direction, in device units. :param y_scale: the scale in the Y direction, in device units. *New in cairo 1.14.* *New in cairocffi 0.9.* """

        cairo.cairo_surface_set_device_scale(self._pointer, x_scale, y_scale)
        self._check_status()