# Install pyston_lite_autoload to ~/.local/lib/python3.10/site-packages/.
$ python3 -m pip install --user pyston_lite_autoload

$ python3 llil2.py big1.txt big2.txt big3.txt > out2.txt
collect time         :    4.3 s
sort+format time     :    3.5 s
total processing time:    7.9 s
output time          :    3.3 s
total time           :   11.2 s