code: func (s *Stream) Bool() (bool, error) {
  	num, err := s.uint(8)
  	if err != nil {
  		return false, err
  	}
  	switch num {
  	case 0:
  		return false, nil
  	case 1:
  		return true, nil
  	default:
  		return false, fmt.Errorf("rlp: invalid boolean value: %d", num)
  	}
  }
docs: // Bool reads an RLP string of up to 1 byte and returns its contents
  // as a boolean. If the input does not contain an RLP string, the
  // returned error will be ErrExpectedString.