anchor.diff:            {
               "attrs": {
                 "pressure": {
  -                "types": [ "none" ]
  +                "types": [ "Number" ]
                 },
                 "humidity": {
                   "types": [ "percentage" ]
  
positive.code:   `null` value. In responses, the value is always present.
  
  * Attribute/metadata `type` may be omitted in requests. When omitted in attribute/metadata creation
    or in update operations, the default string value `none` is used for the type.
  
  * Attribute `metadata` may be omitted in requests, meaning that there are no metadata elements
    associated to the attribute. In responses, this property is set to
  
negative.code:             "metadata": {
                "crs": {
                  "value": "WGS84",
                  "type": "Text"
                }
              }
            }
  