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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 get_new_filename(self, name):
 """Generate filename for new migration."""

        name = MigrationFile.normalize_name(name)
        migrations = self.get_migration_files()
        migration_id = migrations[-1].id if migrations else 0
        migration_id += 1
        return '{:04}_{}.py'.format(migration_id, name)