code: def save(self, checkpoint):
      SafePickle.dump(self.model, open(checkpoint, "wb"))
  
imports: from bigdl.orca.common import SafePickle
  import pandas
  from xgboost.sklearn import XGBRegressor
  from xgboost.sklearn import XGBClassifier
  from bigdl.orca.automl.metrics import Evaluator
  from bigdl.orca.automl.model.abstract import BaseModel, ModelBuilder
  from bigdl.dllib.utils.log4Error import invalidInputError
  import logging
label_desc: Use image node_id 8 for calling the XGBoost obj's underlying member method code with example usage: obj.save(checkpoint) without return types