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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 batch_save(self, *documents):
 """ Inserts or updates every document specified in documents. :param documents: Array of documents to save as dictionaries :type documents: ``array`` of ``dict`` :return: Results of update operation as overall stats :rtype: ``dict`` """

        if len(documents) < 1:
            raise Exception('Must have at least one document.')

        data = json.dumps(documents)

        return json.loads(self._post('batch_save', headers=KVStoreCollectionData.JSON_HEADER, body=data).body.read().decode('utf-8'))