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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 create(self, dataset_name, query, index_by, display_name):
 """ Create a Cached Dataset for a Project. Master key must be set. """

        url = "{0}/{1}".format(self._cached_datasets_url, dataset_name)
        payload = {
            "query": query,
            "index_by": index_by,
            "display_name": display_name
        }
        return self._get_json(HTTPMethods.PUT, url, self._get_master_key(), json=payload)