code: def get_d1nts(self):
          
          data = []
          ntdata = cx.namedtuple("NtPrt", "D1 NS dcnt depth GO name")
          namespace = None
          for ntlet in sorted(self.goone2ntletter.values(),
                              key=lambda nt: [nt.goobj.namespace, -1 * nt.dcnt, nt.D1]):
              goobj = ntlet.goobj
              goid = goobj.id
              assert len(goobj.parents) == 1
              if namespace != goobj.namespace:
                  namespace = goobj.namespace
                  ntns = self.ns2nt[namespace]
                  pobj = ntns.goobj
                  ns2 = self.str2ns[goobj.namespace]
                  data.append(ntdata._make([" ", ns2, ntns.dcnt, pobj.depth, pobj.id, pobj.name]))
              data.append(ntdata._make(
                  [ntlet.D1, self.str2ns[namespace], ntlet.dcnt, goobj.depth, goid, goobj.name]))
          return data
docs: Get letters for depth-01 GO terms, descendants count, and GO information.