no subnet id in ec2_vpc_subnet?

The doco for ec2_vpc_subnet shows no ID attribute for a subnet, except in the return value. I tried a few obvious variants with no luck, just in case it had just been omitted from the doco.

Without an ID attribute, am I supposed to use the (vpc_id, cidr) tuple? That seems very clunky compared to just using a unique ID.

Is there a better way?

Regards, K.