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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 set_idle_priority(pid=None):
 """ Puts a process in the idle io priority class. If pid is omitted, applies to the current process. """


    if pid is None:
        pid = os.getpid()
    lib.ioprio_set(
        lib.IOPRIO_WHO_PROCESS, pid,
        lib.IOPRIO_PRIO_VALUE(lib.IOPRIO_CLASS_IDLE, 0))