query LibraryCustomMetadataPropertiesPermissions {
  library(id: "…") {
    customMetadataProperties {
      permissions {
        __typename
        basic {
          permissionLevel
          subject
        }
        custom {
          permissionLevel
          subject {
            __typename
            ... on AccountUser { id }
            ... on UserGroup { id }
          }
        }
      }
    }
  }
}