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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 _guess_iface_name(netif):
 """ We attempt to guess the name of interfaces that are truncated from the output of ifconfig -l. If there is only one possible candidate matching the interface name then we return it. If there are none or more, then we return None. """

    with os.popen('%s -l' % conf.prog.ifconfig) as fdesc:
        ifaces = fdesc.readline().strip().split(' ')
    matches = [iface for iface in ifaces if iface.startswith(netif)]
    if len(matches) == 1:
        return matches[0]
    return None