如何在CDK中为SNS主题添加订阅过滤器

from aws_cdk import core
from aws_cdk import aws_sns as sns

class MyStack(core.Stack):
    def __init__(self, scope: core.Construct, id: str, **kwargs) -> None:
        super().__init__(scope, id, **kwargs)

        # 创建SNS主题
        topic = sns.Topic(self, "MyTopic")

        # 创建订阅过滤器
        filter_policy = {
            "color": sns.SubscriptionFilter.string_filter(whitelist=["red", "blue"]),
            "size": sns.SubscriptionFilter.numeric_filter(less_than=10)
        }

        # 为SNS主题添加订阅过滤器
        topic.add_subscription_filter("MyFilter", filter_policy)

app = core.App()
MyStack(app, "my-stack")
app.synth()