code: def fix_list_arguments(self):
          
          either = [list(c.children) for c in self.either.children]
          for case in either:
              case = [c for c in case if case.count(c) > 1]
              for a in [e for e in case if type(e) == Argument]:
                  a.value = []
          return self
docs: Find arguments that should accumulate values and fix them.