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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:
 async def scale(self, application, scale):
 """ Handle a change of scale to a k8s application. :param string application: Application holds the application placeholder name for which a unit is added. :param int scale: New scale value to use. """

        application = self.resolve(application)
        return await self.model.applications[application].scale(scale=scale)