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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 ip_v6_network_validator(v: Any) -> IPv6Network: """ Assume IPv6Network initialised with a default ``strict`` argument See more: https://docs.python.org/library/ipaddress.html#ipaddress.IPv6Network """

    if isinstance(v, IPv6Network):
        return v

    with change_exception(errors.IPv6NetworkError, ValueError):
        return IPv6Network(v)