I’m new to aws cdk. I’m trying to create a bucket and then later on read its arn so I can use it in an iam policy. The output is not what I’d expect. (I’m writing the app in python)

bucket_construct = s3.Bucket(self, 'MyBucket')

my_bucket_arn = bucket_construct.bucket_arn

The output for my_bucket_arn in the output after synth is not what I’d expect I’m getting: { "Fn::GetAtt": ["MyBucketCF081867","Arn"]}

Why can’t I get the arn… something like: arn:aws:s3:::MyBucketCF081867?