Update self.evaluated_individuals_ and error message during pipeline evaluation.

        Parameters
        ----------
        result_score_list: list
            A list of CV scores for evaluated pipelines
        eval_individuals_str: list
            A list of strings for evaluated pipelines
        operator_counts: dict
            A dict where 'key' is the string representation of an individual and 'value' is the number of operators in the pipeline
        stats_dicts: dict
            A dict where 'key' is the string representation of an individual and 'value' is a dict containing statistics about the individual


        Returns
        -------
        None

def _update_evaluated_individuals_(self, result_score_list, eval_individuals_str, operator_counts, stats_dicts):
        """Update self.evaluated_individuals_ and error message during pipeline evaluation.

        Parameters
        ----------
        result_score_list: list
            A list of CV scores for evaluated pipelines
        eval_individuals_str: list
            A list of strings for evaluated pipelines
        operator_counts: dict
            A dict where 'key' is the string representation of an individual and 'value' is the number of operators in the pipeline
        stats_dicts: dict
            A dict where 'key' is the string representation of an individual and 'value' is a dict containing statistics about the individual


        Returns
        -------
        None
        """
        for result_score, individual_str in zip(result_score_list, eval_individuals_str):
            if type(result_score) in [float, np.float64, np.float32]:
                self.evaluated_individuals_[individual_str] = self._combine_individual_stats(operator_counts[individual_str],
                                                                                             result_score,
                                                                                             stats_dicts[individual_str])
            else:
                raise ValueError('Scoring function does not return a float.')