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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 in6_addrtomac(addr):
 """ Extract the mac address from provided address. None is returned on error. """

    mask = inet_pton(socket.AF_INET6, "::ffff:ffff:ffff:ffff")
    x = in6_and(mask, inet_pton(socket.AF_INET6, addr))
    ifaceid = inet_ntop(socket.AF_INET6, x)[2:]
    return in6_ifaceidtomac(ifaceid)