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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_cmdsets(job, cmdsets, depth):
 """Creates a list of sets containing jobs at different depths of the dependency tree. This is a recursive function (is there something quicker in the itertools module?) that descends each 'root' job in turn, populating each """

    if len(cmdsets) < depth:
        cmdsets.append(set())
    cmdsets[depth-1].add(job.command)
    if len(job.dependencies) == 0:
        return cmdsets
    for j in job.dependencies:
        cmdsets = populate_cmdsets(j, cmdsets, depth+1)
    return cmdsets