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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 get_image_size(self, image):
 """ Returns the image width and height as a tuple """

        if image['size'] is None:
            args = settings.THUMBNAIL_VIPSHEADER.split(' ')
            args.append(image['source'])
            p = subprocess.Popen(args, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
            p.wait()
            m = size_re.match(str(p.stdout.read()))
            image['size'] = int(m.group('x')), int(m.group('y'))
        return image['size']