def METHOD_NAME(self, df: PandasData):
    """Creates placeholder column names for dataframes without column names.
    Args:
        df (pd.DataFrame):
            Required. This is the dataframe to serialize.
    """
    if isinstance(df.columns, pd.RangeIndex):
        df.columns = [str(x) for x in df.columns]
        self.restore_df_actions.append("remove_placeholder_col_names")
        self.restore_df_actions_args.append([])