Using objects and decorators instead of classes with just one method and some constants

cleanupjob_class.py

from job_class import Job

def delete_expired_stuff(time):
    print "Delete expired stuff before %s" % time

class CleanupJob(Job):
    # configuration: run at 5am
    run_at = '05:00'

    # implementation: nuke expired sessions
    def run(self):
        delete_expired_stuff(self.run_at)

if __name__ == '__main__':
    CleanupJob().run()

cleanupjob_object.py

from job_object import Job

def delete_expired_stuff(time):
    print "Delete expired stuff before %s" % time

job = Job(run_at='05:00')

@job.run
def do_cleanup(job):
    delete_expired_stuff(job.run_at)

if __name__ == '__main__':
    job.run()

job_class.py

class Job(object):
    run_at = None
    
    def __init__(self):
        print "Scheduled at %s" % self.run_at

    def run(self):
        raise NotImplementedError

job_object.py

class Job(object):
    def __init__(self, run_at):
        self.run_at = run_at
        print "Scheduled at %s" % run_at

    def _func(self, job):
        raise NotImplementedError

    def run(self, func=None):
        if func is not None:
            self._func = func
            return func
        return self._func(self)