code: def get_usrgo2sections(self):
          
          usrgo2sections = cx.defaultdict(set)
          usrgo2hdrgo = self.get_usrgo2hdrgo()
          get_sections = self.hdrobj.get_sections
          for usrgo, hdrgo in usrgo2hdrgo.items():
              sections = set(get_sections(hdrgo))
              usrgo2sections[usrgo] |= sections
          assert len(usrgo2sections) >= len(self.usrgos), \
              "uGOS({U}) != uGO2sections({H}): {GOs}".format(
                  U=len(self.usrgos),
                  H=len(usrgo2sections),
                  GOs=self.usrgos.symmetric_difference(set(usrgo2sections.keys())))
          return usrgo2sections
docs: Return a dict with all user GO IDs as keys and their sections as values.