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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 validate_cidr(s):
 """Validate a CIDR notation ip address. The string is considered a valid CIDR address if it consists of a valid IPv6 address in hextet format followed by a forward slash (/) and a bit mask length (0-128). True True True True False False Traceback (most recent call last):
 TypeError: expected string or buffer :param s: String to validate as a CIDR notation ip address. :type s: str :returns: ``True`` if a valid CIDR address, ``False`` otherwise. :raises: TypeError """

    if _CIDR_RE.match(s):
        ip, mask = s.split('/')
        if validate_ip(ip):
            if int(mask) > 128:
                return False
        else:
            return False
        return True
    return False