How to use the ciscoconfparse.local_py.ipaddr._BaseNet function in ciscoconfparse

def __contains__(self, other):
        # always false if one is v4 and the other is v6.
        if self._version != other._version:
          return False
        # dealing with another network.
        if isinstance(other, _BaseNet):
            return (self.network <= other.network and
                    self.broadcast >= other.broadcast)
        # dealing with another address
        else:
            return (int(self.network) <= int(other._ip) <=
                    int(self.broadcast))

IPv6Network((0x20010db8 << 96, 128))
                IPv6Network((IPv6Address('2001:db8::'), 128))

            strict: A boolean. If true, ensure that we have been passed
              A true network address, eg, 2001:db8::/32 and not an
              IP address on a network, eg, 2001:db8::1/32.

        Raises:
            AddressValueError: If address isn't a valid IPv6 address.
            NetmaskValueError: If the netmask isn't valid for
              an IPv6 address.
            ValueError: If strict was True and a network address was not
              supplied.

        """
        _BaseNet.__init__(self, address)
        _BaseV6.__init__(self, address)

        # Constructing from a single IP address.
        if isinstance(address, (int, long, Bytes, IPv6Address)):
            self.ip = IPv6Address(address)
            self._ip = self.ip._ip
            self._prefixlen = self._max_prefixlen
            self.netmask = IPv6Address(self._ALL_ONES)
            return

        # Constructing from an (ip, prefixlen) tuple.
        if isinstance(address, tuple):
            try:
                ip, prefixlen = address
            except ValueError:
                raise AddressValueError(address)

Returns:
            A string, the expanded IPv6 address.

        """
        if isinstance(self, _BaseNet):
            ip_str = str(self.ip)
        else:
            ip_str = str(self)

        ip_int = self._ip_int_from_string(ip_str)
        parts = []
        for i in xrange(self._HEXTET_COUNT):
            parts.append('%04x' % (ip_int & 0xFFFF))
            ip_int >>= 16
        parts.reverse()
        if isinstance(self, _BaseNet):
            return '%s/%d' % (':'.join(parts), self.prefixlen)
        return ':'.join(parts)

# Constructing from a packed address
        if isinstance(address, Bytes):
            try:
                hi, lo = struct.unpack('!QQ', address)
            except struct.error:
                raise AddressValueError(address)  # Wrong length.
            self._ip = (hi << 64) | lo
            return

        # Assume input argument to be string or any object representation
        # which converts into a formatted IP string.
        addr_str = str(address)
        self._ip = self._ip_int_from_string(addr_str)


class IPv6Network(_BaseV6, _BaseNet):

    """This class represents and manipulates 128-bit IPv6 networks.

    Attributes: [examples for IPv6('2001:658:22A:CAFE:200::1/64')]
        .ip: IPv6Address('2001:658:22a:cafe:200::1')
        .network: IPv6Address('2001:658:22a:cafe::')
        .hostmask: IPv6Address('::ffff:ffff:ffff:ffff')
        .broadcast: IPv6Address('2001:658:22a:cafe:ffff:ffff:ffff:ffff')
        .netmask: IPv6Address('ffff:ffff:ffff:ffff::')
        .prefixlen: 64

    """


    def __init__(self, address, strict=False):
        """Instantiate a new IPv6 network object.

else:
                # If we got here, there's a bug somewhere.
                assert True == False, ('Error performing exclusion: '
                                       's1: %s s2: %s other: %s' %
                                       (str(s1), str(s2), str(other)))
        if s1 == other:
            ret_addrs.append(s2)
        elif s2 == other:
            ret_addrs.append(s1)
        else:
            # If we got here, there's a bug somewhere.
            assert True == False, ('Error performing exclusion: '
                                   's1: %s s2: %s other: %s' %
                                   (str(s1), str(s2), str(other)))

        return sorted(ret_addrs, key=_BaseNet._get_networks_key)