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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 put(self, path=''):
 """Publish a notebook on a given path. The payload directly matches the contents API for PUT. """

        self.log.info("Attempt publishing to %s", path)

        if path == '' or path == '/':
            raise web.HTTPError(400, "Must provide a path for publishing")

        model = self.get_json_body()
        if model:
            await self._publish(model, path.lstrip('/'))
        else:
            raise web.HTTPError(400, "Cannot publish an empty model")