code: def import_pb2_dependencies():
      try:
          import GPy
      except ImportError:
          GPy = None
      try:
          import sklearn
      except ImportError:
          sklearn = None
      return GPy, sklearn
  
imports: from typing import Callable, Dict, Optional, Tuple, Union, TYPE_CHECKING
  from copy import deepcopy
  import logging
  import numpy
  import pandas
  from ray.tune import TuneError
  from ray.tune.experiment import Trial
  from ray.tune.schedulers import PopulationBasedTraining
  from ray.tune.schedulers.pbt import _PBTTrialState
  from ray.tune.utils.util import flatten_dict, unflatten_dict
  from ray.util.debug import log_once
label_desc: Use image node_id 1 for calling a global function with example usage: import_pb2_dependencies() and returns: GPy,  sklearn