code: def wr_py_sections(self, fout_py, sections, doc=None):
          
          if sections is None:
              sections = self.grprobj.get_sections_2d()
          sec2d_nt = self.get_sections_2dnt(sections)  # lists of GO Grouper namedtuples
          with open(fout_py, 'w') as prt:
              self._prt_py_sections(sec2d_nt, prt, doc)
              dat = SummarySec2dHdrGos().summarize_sec2hdrgos(sections)
              sys.stdout.write(self.grprobj.fmtsum.format(
                  GO_DESC='hdr', SECs=len(dat['S']), GOs=len(dat['G']),
                  UNGRP=len(dat['U']), undesc="unused",
                  ACTION="WROTE:", FILE=fout_py))
docs: Write sections 2-D list into a Python format list.