class_docstr: Blackbox Optimiser Class. 
class_docstr_tok: ["Blackbox","Optimiser","Class","."]
docstr: Return data to save. 
docstr_tok: ["Return","data","to","save","."]
code: def _exd_child_get_data_to_save(self):
      """Return data to save."""
      ret = {
          "points": self.prev_eval_points + self.history.query_points,
          "vals": self.prev_eval_vals + self.history.query_vals,
          "true_vals": self.prev_eval_true_vals
          + self.history.query_true_vals,
      }
      if self.func_caller.is_mf():
          ret["fidels"] = (
              self.prev_eval_fidels + self.history.query_fidels
          )
      num_data_saved = len(ret["points"])
      return ret, num_data_saved
  
imports: from __future__ import division
  from argparse import Namespace
  import numpy
  from ..exd.exd_core import ExperimentDesigner, exd_core_args
  from ..utils.option_handler import load_options
label_desc: Use image node_id 15 for calling the BlackboxOptimiser obj's underlying member method code with example usage: obj._exd_child_get_data_to_save() and returns: ret,  num_data_saved