docs: def record_diff(old, new):
      """Return a JSON-compatible structure capable turn the `new` record back
      into the `old` record. The parameters must be structures compatible with
      json.dumps *or* strings compatible with json.loads. Note that by design,
      `old == record_patch(new, record_diff(old, new))`"""
      old, new = _norm_json_params(old, new)
      return json_delta.diff(new, old, verbose=False)