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* Replaced ``settings.NETWORK_INTERCONNECT_PREFIXLEN`` (an integer) with
``settings.NETWORK_INTERCONNECT_PREFIXES`` (a tuple) to support IPv6
prefixes, which defaults to prefixes (/31, /127).
* ``Network.next_address()`` was changed to calculate available addresses
differently if the network from which you are allocating is determined to be
an interconnect network. For interconnects, gateway and broadcast addresses
can be returned. For any other networks, they cannot.