@property
    def default_alias(self):
        expressions = self.get_source_expressions()
        if len(expressions) == 1 and hasattr(expressions[0], 'name'):
            return (expressions[0].name, self.name.lower()) % '%s__%s'
        raise TypeError("Complex expressions require an alias")
dataset/ETHPy150Open django/django/django/db/models/aggregates.py/Aggregate.default_alias/swapped operands of `%`