I created an arpa format lm using CMU-LM_Toolkit and converted it to G.fst using 'arpa2fst --disambig-symbol=#0 cmu.arpa G.fst'.
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--> data/lang/G.fst is determinizable
FATAL: FstCompiler: Bad arc ilabel integer = "#0", source = standard input, line = 1
ERROR: FstHeader::Read: Bad FST header: standard input
--> ERROR: failure running
check_g_properties.pl--> Testing determinizability of L_disambig . G
fstdeterminizestar
fsttablecompose data/lang/L_disambig.fst data/lang/G.fst
--> L_disambig . G is determinizable
--> ERROR (see error messages above)
prepare_lang.sh: error validating output
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