'Prints a report around DagBag loading stats'

def dagbag_report(self):

    report = textwrap.dedent(u'\n\n                                -------------------------------------------------------------------\n                                DagBag    loading    stats    for    {dag_folder}\n                                -------------------------------------------------------------------\n                                Number    of    DAGs:    {dag_num}\n                                Total    task    number:    {task_num}\n                                DagBag    parsing    time:    {duration}\n                                {table}\n                                ')
    stats = self.dagbag_stats
    return report.format(dag_folder=self.dag_folder, duration=sum([o.duration for o in stats]), dag_num=sum([o.dag_num for o in stats]), task_num=sum([o.dag_num for o in stats]), table=pprinttable(stats))
