code: def label_hierarchy_level_to_str(self, label_hierarchy_level):
      if c_f.is_list_or_tuple(label_hierarchy_level):
          return "_".join(str(x) for x in label_hierarchy_level)
      else:
          return str(label_hierarchy_level)
  
imports: from collections import defaultdict
  import torch
  import tqdm
  from ..utils import common_functions
  from ..utils import inference
  from ..utils.accuracy_calculator import AccuracyCalculator
label_desc: Use image node_id 11 for calling the BaseTester obj's underlying member method code with example usage: obj.label_hierarchy_level_to_str(label_hierarchy_level) and returns: str, str