code: def __init__(self, max_loc, base_path):
      super().__init__(max_loc)
      self.db_path = base_path
  
      if not PathManager.exists(self.db_path):
          raise RuntimeError(
              "{} path specified for LMDB features doesn't exists.".format(
                  self.db_path
              )
          )
      self.env = None
  
imports: import math
  import os
  import pickle
  from typing import Any
  import lmdb
  import numpy
  import torch
  from mmf.utils.file_io import PathManager
label_desc: Use image node_id 1 to create a new LMDBFeatureReader object from inherited base classes: PaddedFasterRCNNFeatureReader with example: obj = LMDBFeatureReader(max_loc, base_path)