code: def _str_targets(self):
          
          def _slice_to_str(obj):
              if isinstance(obj, slice):
                  start = "" if obj.start is None else str(obj.start.__index__())
                  stop = "" if obj.stop is None else str(obj.stop.__index__())
                  if obj.step is None:
                      return f"{start}:{stop}"
                  else:
                      step = str(obj.step.__index__())
                      return f"{start}:{stop}:{step}"
              else:
                  return obj.__index__()
  
          if isinstance(self.targets, tuple):
              return f"[{', '.join(_slice_to_str(idx for idx in self.targets))}]"
          else:
              return f"[{_slice_to_str(self.targets)}]"
docs: Returns printable string of targets.