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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 close(self):
 """Commit changes and close the database."""

        import sys, os
        for store in self.stores:
            if hasattr(store, 'save'):
                store.save(reimport=False)
            path, filename = os.path.split(store._filename)
            modname = filename[:-3]
            if modname in sys.modules:
                del sys.modules[modname]
        super().close()