Correct syntax of export_library


I found in this page that it is (used to be?) possible to save a .cc file with the library of a compiled graph. But I get tons of errors when I try to use export_library, so can anyone tell me what is the correct syntax? Is this still valid with Relay or was it a feature only supported in NNVM?

This script actually works:

opt_level = 3
target = 'llvm --system-lib'
with relay.build_config(opt_level=opt_level):
    graph, lib, params =
        mod, target, params=params)

lib.export_library("deploy.tar", fcompile=False)

but in the .tar archive I can find only a .o file, not a .cc! What options am I missing?