code: def _get_parsing_plan_for_multifile_children(self, obj_on_fs: PersistedObject, desired_type: Type[Any],
                                                   logger: Logger) -> Dict[str, Any]:
          
          # nb of file children
          n_children = len(obj_on_fs.get_multifile_children())
  
          # first extract base collection type
          subtypes, key_type = _extract_collection_base_type(desired_type)
  
          if isinstance(subtypes, tuple):
              # -- check the tuple length
              if n_children != len(subtypes):
                  raise FolderAndFilesStructureError.create_for_multifile_tuple(obj_on_fs, len(subtypes),
                                                                                len(obj_on_fs.get_multifile_children()))
          else:
              # -- repeat the subtype n times
              subtypes = [subtypes] * n_children
  
          # -- for each child create a plan with the appropriate parser
          children_plan = OrderedDict()
          # use sorting for reproducible results in case of multiple errors
          for (child_name, child_fileobject), child_typ in zip(sorted(obj_on_fs.get_multifile_children().items()),
                                                             subtypes):
              # -- use the parserfinder to find the plan
              t, child_parser = self.parser_finder.build_parser_for_fileobject_and_desiredtype(child_fileobject, 
                                                                                               child_typ, logger)
              children_plan[child_name] = child_parser.create_parsing_plan(t, child_fileobject, logger,
                                                                           _main_call=False)
  
          return children_plan
docs: Simply inspects the required type to find the base type expected for items of the collection,
          and relies on the ParserFinder to find the parsing plan
  
          :param obj_on_fs:
          :param desired_type:
          :param logger:
          :return: