code: def _close_oldest_model(self):
      if len(self.loaded_models):
          name = self.loaded_models.pop(0)
          self.model_cache[name].close()
          del self.model_cache[name]
          gc.collect()
      else:
          LOGGER.info("No models cached -- cannot remove oldest model.")
  
imports: from collections import OrderedDict
  import gc
  import logging
  import functools
  import psutil
  from finetune.target_models.sequence_labeling import SequenceLabeler
  import tensorflow
  from finetune.base import BaseModel
  from finetune.custom_ops import BytesInUse, BytesLimit, MaxBytesInUse
  from finetune.errors import FinetuneSchedulerError
label_desc: Use image node_id 3 for calling the Scheduler obj's underlying member method code with example usage: obj._close_oldest_model() without return types