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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 cleanup(self):
 """ Performs clean-up after task is completed before it is executed again in the next internal. """

        # Closes connections to all databases to avoid the long running process
        # from holding connections indefinitely.
        for alias in db.connections.databases:
            logger.info('Closing database connection: %s', alias)
            db.connections[alias].close()