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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_jobs(self, job_ids = None):
 """Returns a list of jobs that are stored in the database."""

    if job_ids is not None and len(job_ids) == 0:
      return []
    q = self.session.query(Job)
    if job_ids is not None:
      q = q.filter(Job.unique.in_(job_ids))
    return sorted(list(q), key=lambda job: job.unique)