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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 populate_jobset(job, jobset, depth):
 """ Creates a set of jobs, containing jobs at difference depths of the dependency tree, retaining dependencies as strings, not Jobs. """

    jobset.add(job)
    if len(job.dependencies) == 0:
        return jobset
    for j in job.dependencies:
        jobset = populate_jobset(j, jobset, depth+1)
    return jobset