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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 refresh(self):
 """ Clears the composition and renders all the images taking into account their position and offset. """

        self._clear()
        for img in self.composed_images:
            self._background_image.paste(img.image(self._device.size),
                                         img.position)
        self._background_image.crop(box=self._device.bounding_box)