A netlist is a list of the connections between the various components/pins in a schematic/PCB.
Why do you want to import one to Eagle? Eagle doesn't use "external" netlists - all the interconnections are contained within the .sch & .brd files. In the past most PCB packages were separate from the schematic package even if they were from the same vendor and the netlist was the way of transferring the connectivity between the two separate bits of software. Some still work like that. However, Eagle doesn't.
Keith