ref: b117d7014da620fb2aa8de900c2c4a57fefe5f19
dir: /sys/src/cmd/python/Tools/bgen/README/
BGEN -- Automatic Generation of Extension Modules ================================================= This directory contains BGEN -- a package that helps in generating complete source code for Python extension module. For examples of its use, see the Mac Python source distribution (available separately from the Python ftp archives). Note that BGEN is not Mac specific!