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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 main():
 """ Use threads and Netmiko to connect to each of the devices. Execute 'show version' on each device. Record the amount of time required to do this. """

    start_time = datetime.now()

    for a_device in devices:
        my_thread = threading.Thread(target=show_version, args=(a_device,))
        my_thread.start()

    main_thread = threading.currentThread()
    for some_thread in threading.enumerate():
        if some_thread != main_thread:
            print(some_thread)
            some_thread.join()

    print("\nElapsed time: " + str(datetime.now() - start_time))