How to use the matminer.featurizers.conversions.DictToObject function in matminer

else:
            # Convert structure/bs/dos dicts to objects (robust already)
            if isinstance(type_tester, (dict, str)):
                logger.info(
                    self._log_prefix.capitalize()
                    + "{} detected as string or dict. Attempting "
                    "conversion to {} objects..."
                    "".format(featurizer_type, featurizer_type)
                )
                if isinstance(type_tester, str):
                    raise ValueError(
                        "{} column is type {}. Cannot convert."
                        "".format(featurizer_type, type(type_tester))
                    )
                dto = DictToObject(
                    overwrite_data=True, target_col_id=featurizer_type
                )
                dto.set_n_jobs(self.n_jobs)
                df = dto.featurize_dataframe(df, featurizer_type, inplace=False)

            # Decorate with oxidstates
            if featurizer_type == self.structure_col and self.guess_oxistates:
                logger.info(
                    self._log_prefix
                    + "Guessing oxidation states of structures if they were "
                    "not present in input."
                )
                sto = StructureToOxidStructure(
                    target_col_id=featurizer_type,
                    overwrite_data=True,
                    return_original_on_error=True,