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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_6to4ExtractAddr(addr):
 """ Extract IPv4 address embbeded in 6to4 address. Passed address must be a 6to4 addrees. None is returned on error. """

    try:
        addr = inet_pton(socket.AF_INET6, addr)
    except:
        return None
    if addr[:2] != b" \x02":
        return None
    return inet_ntop(socket.AF_INET, addr[2:6])