code: def add(self, idx):
      self.cnt += 1
      if idx == -1:
          return
      for i in range(self.LEN):
          if idx < self.rank[i]:
              self.hits[i] += 1
  
imports: import json
  import torch
label_desc: Use image node_id 2 for calling the Stats obj's underlying member method code with example usage: obj.add(idx) without return types