text: import logging
  
  logger = logging.getLogger(__name__)
  
  train = None
  predict = None
  RayParams = None
  RayDMatrix = None
  RayFileType = None
  RayXGBClassifier = None
  RayXGBRegressor = None
  RayXGBRFClassifier = None
  RayXGBRFRegressor = None
  
  try:
      from xgboost_ray import (train, predict, RayParams, RayDMatrix,
                               RayFileType, RayXGBClassifier, RayXGBRegressor,
                               RayXGBRFClassifier, RayXGBRFRegressor)
  except ImportError:
      logger.info(
          "xgboost_ray is not installed. Please run "
          "`pip install git+https://github.com/ray-project/xgboost_ray`.")
  
  __all__ = [
      "train", "predict", "RayParams", "RayDMatrix", "RayFileType",
      "RayXGBClassifier", "RayXGBRegressor", "RayXGBRFClassifier",
      "RayXGBRFRegressor"
  ]
  