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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 cmd_merge(self):
 """Merge migrations."""

        from peewee_migrate.router import Router, LOGGER

        LOGGER.setLevel('DEBUG')
        LOGGER.propagate = 0

        router = Router(self.database,
                        migrate_dir=self.app.config['PEEWEE_MIGRATE_DIR'],
                        migrate_table=self.app.config['PEEWEE_MIGRATE_TABLE'])

        router.merge()