Use union typing when return types differs and remove commented code
-rw-r--r-- 55 .gitignore
-rw-r--r-- 0 BUILD.bazel
-rw-r--r-- 158 Makefile
-rw-r--r-- 579 README.md
-rw-r--r-- 1086 WORKSPACE
-rw-r--r-- 61 requirements.txt
drwxr-xr-x - src