How to parse SGF files analyzed by ELF GO

[mibastro]

Hi, I want to ask for more detailed information about SGF files provided in the Facebook elf-go tools.

https://ai.facebook.com/tools/elf-opengo
In the above link, SGF files analyzed by elf-go are provided and I want to analyze those files.
More specifically SGF files in the link below.
https://dl.fbaipublicfiles.com/elfopengo/analysis/data/gogod_commentary_sgfs.gzip

The format is slightly different from typical SGF files. Each line in the recorded move includes additional tree structured information generated by elf-go.
But I cannot find detailed information about the format of the file nor how to parse them.
Can I get a parser for these files? Or any detailed instructions on how to parse them correctly?

Thank you.