docs: def to_csvf(self, fpath: str, fieldnames: Sequence[str], encoding: str='utf8',
                  with_header: bool=False, crlf: bool=False, tsv: bool=False) -> str:
          """From instance to yaml file
  
          :param fpath: Csv file path
          :param fieldnames: Order of columns by property name
          :param encoding: Csv file encoding
          :param with_header: Add headers at the first line if True
          :param crlf: Add CRLF line break at the end of line if True, else add LF
          :param tsv: Use tabs as separator if True, else use comma
          :return: Csv file path
          """
          return util.save_csvf(traverse(self, force_value=True), fieldnames, fpath, encoding, with_header, crlf, tsv)