code: def _clear_cache(self):
      pass
  
imports: import contextlib
  import warnings
  import sys
  import torch
  from .None import utils
  from .opt import OptimWrapper
  from .scaler import LossScaler
  from ._amp_state import _amp_state, master_params, maybe_print
label_desc: Use image node_id 7 for calling the NoOpHandle obj's underlying member method code with example usage: obj._clear_cache() without return types