NetPort
NetPort["port"] represents the specified input or output port for a complete net.
NetPort[{n,"port"}] represents the specified port for layer number n in a NetGraph or similar construct.
NetPort[{"name","port"}] represents the specified port for the layer with the specified name.
NetPort[spec,port] is treated as equivalent to NetPort[{spec,port}].
NetPort[{spec1,spec2,…,"port"}] permits access to the port of nested layers in a NetGraph or a NetChain.
NetPort[All,"States"] represents the set of all states in a net associated with recurrent layers such as LongShortTermMemoryLayer.
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