code: def get_lines(data_nts, prtfmt=None, nt_fields=None, **kws):
      
      lines = []
      # optional keyword args: prt_if sort_by
      if prtfmt is None:
          prtfmt = mk_fmtfld(data_nts[0], kws.get('joinchr', ' '), kws.get('eol', '\n'))
      # if nt_fields arg is None, use fields from prtfmt string.
      if nt_fields is not None:
          _chk_flds_fmt(nt_fields, prtfmt)
      if 'sort_by' in kws:
          data_nts = sorted(data_nts, key=kws['sort_by'])
      prt_if = kws.get('prt_if', None)
      for data_nt in data_nts:
          if prt_if is None or prt_if(data_nt):
              lines.append(prtfmt.format(**data_nt._asdict()))
      return lines
docs: Print list of namedtuples into a table using prtfmt.