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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 discover_thread(callback, timeout=5, include_invisible=False, interface_addr=None):
 """ Return a started thread with a discovery callback. """

    thread = StoppableThread(
        target=_discover_thread,
        args=(callback, timeout, include_invisible, interface_addr))
    thread.start()
    return thread