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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 _add_image_part(self, image):
 """ Return an |ImagePart| instance newly created from image and appended to the collection. """

        partname = self._next_image_partname(image.ext)
        image_part = ImagePart.from_image(image, partname)
        self.append(image_part)
        return image_part