code: func (kv KeyValue) bool(name string, defaultValue bool) bool {
  	if v, found := kv[name]; found {
  		if castValue, is := v.(bool); is {
  			return castValue
  		}
  	}
  	return defaultValue
  }
docs: // bool returns the value of the given name, assuming the value is a boolean.
  // If the value isn't found or is not of the type, the defaultValue is returned.