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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 srp(x, promisc=None, iface=None, iface_hint=None, filter=None, nofilter=0, type=ETH_P_ALL, *args, **kargs):
 """Send and receive packets at layer 2"""

    if iface is None and iface_hint is not None:
        iface = conf.route.route(iface_hint)[0]
    s = conf.L2socket(promisc=promisc, iface=iface,
                      filter=filter, nofilter=nofilter, type=type)
    result = sndrcv(s, x, *args, **kargs)
    s.close()
    return result