'This returns the age of the oldest job in the queue in normal waiting
state'

def oldest_queued_job_age(self):

    for j in self.jobs:
        if (('JB_submission_time' in j) and (j['state'] == 'qw')):
            st = j['JB_submission_time']
            dt = utils.iso_to_datetime_tuple(st)
            return dt.replace(tzinfo=self.remote_tzinfo)
