How do you add a comment to a json IAM policy?

IAM policy are complicated beasts. It would be nice to add a comment when crafting them. For example,

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Sid": "Stmt1422979261000",
      "Effect": "Allow",
      "Action": [
        "route53:ListHostedZones",
      ],
      "Comment": "Foo"
      # or Bar
      "Resource": [
        "*"
      ]
    }
  ]
}

Neither of these work. Does there exist a way to add comments to these policies?