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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 ensure_indexes(self):
 """Update the indexes"""

        for collection_name in INDEXES:
            existing_indexes = self.indexes(collection_name)
            indexes = INDEXES[collection_name]
            for index in indexes:
                index_name = index.document.get('name')
                if index_name in existing_indexes:
                    logger.debug("Index exists: %s" % index_name)
                    self.db[collection_name].drop_index(index_name)
            logger.info("creating indexes for collection {0}: {1}".format(
                collection_name,
                ', '.join([index.document.get('name') for index in indexes]),
                )
            )
            self.db[collection_name].create_indexes(indexes)