Write xlsx table of depth-01 GO terms and their letter representation.

def wr_xlsx(self, fout_xlsx="gos_depth01.xlsx", **kws):
        """Write xlsx table of depth-01 GO terms and their letter representation."""
        data_nts = self.get_d1nts()
        if 'fld2col_widths' not in kws:
            kws['fld2col_widths'] = {'D1': 6, 'NS':3, 'depth': 5, 'GO': 12, 'name': 40}
        if 'hdrs' not in kws:
            kws['hdrs'] = self.hdrs
        wr_xlsx_tbl(fout_xlsx, data_nts, **kws)