code: func NestedBool(obj map[string]interface{}, fields ...string) (bool, bool, error) {
  	val, found, err := NestedFieldNoCopy(obj, fields...)
  	if !found || err != nil {
  		return false, found, err
  	}
  	b, ok := val.(bool)
  	if !ok {
  		return false, false, fmt.Errorf("%v accessor error: %v is of the type %T, expected bool", jsonPath(fields), val, val)
  	}
  	return b, true, nil
  }
docs: // NestedBool returns the bool value of a nested field.
  // Returns false if value is not found and an error if not a bool.