code: def get_dataset(self, key):
      return self._key_to_dataset[key]
  
file_path: horovod/horovod/spark/common/cache.py
imports: import collections
  import contextlib
  import threading
label_desc: Use image node_id 5 for calling the TrainingDataCache obj's underlying member method code with example usage: obj.get_dataset(key) and returns: self