code: def get_wbfmt(self, data_nt=None):
          
          if data_nt is None or self.b_plain:
              return self.fmtname2wbfmtobj.get('plain')
          # User namedtuple field/value for color
          if self.ntfld_wbfmt is not None:
              return self.__get_wbfmt_usrfld(data_nt)
          # namedtuple format_txt for color/bold/border
          if self.b_format_txt:
              wbfmt = self.__get_wbfmt_format_txt(data_nt)
              if wbfmt is not None:
                  return wbfmt
          # 'ntfld_wbfmt': namedtuple field which contains a value used as a key for a xlsx format
          # 'ntval2wbfmtdict': namedtuple value and corresponding xlsx format dict.
          return self.fmtname2wbfmtobj.get('plain')
docs: Return format for text cell.