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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_max_item(self, expand=False):
 """The current largest item id Fetches data from URL: https://hacker-news.firebaseio.com/v0/maxitem.json Args: expand (bool):
 Flag to indicate whether to transform all IDs into objects. Returns: `int` if successful. """

        url = urljoin(self.base_url, 'maxitem.json')
        response = self._get_sync(url)
        if expand:
            return self.get_item(response)
        else:
            return response