def update_output_mintime(job):
    try:
        return output_mintime[job]
    except KeyError:
        for job_ in chain([job], self.depending[job]):
            try:
                t = output_mintime[job_]
            except KeyError:
                t = job_.output_mintime
            if (t is not None):
                output_mintime[job] = t
                return
        output_mintime[job] = None
def update_output_mintime(job):
    try:
        return output_mintime[job]
    except KeyError:
        for job_ in chain([job], self.depending[job]):
            try:
                t = output_mintime[job_]
            except KeyError:
                t = job_.output_mintime
            if (t is not None):
                output_mintime[job] = t
                return
        output_mintime[job] = None