code: def create_optuna_backend():
      """Create an Optuna Backend."""
      from bigdl.nano.deps.automl.optuna_backend import OptunaBackend
  
      return OptunaBackend()
  
file_path: BigDL/python/nano/src/bigdl/nano/deps/automl/hpo_api.py
imports: import warnings
label_desc: Use image node_id 3 for calling a global function with example usage: create_optuna_backend() and returns: OptunaBackend