docs: def get_contextualize_items_by_step(self, default=None):
          """Get a dictionary of the contextualize_items grouped by the step or the default value"""
          if self.items:
              res = {}
              for elem in self.items.values():
                  if elem.num in res:
                      res[elem.num].append(elem)
                  else:
                      res[elem.num] = [elem]
              return res
          else:
              return default