# Source Code Layout

For modules:

• Lib/<module>.py

• Modules/_<module>module.c (if there’s also a C accelerator module)

• Lib/test/test_<module>.py

• Doc/library/<module>.rst

For extension-only modules, the typical layout is:

• Modules/<module>module.c

• Lib/test/test_<module>.py

• Doc/library/<module>.rst

For builtin types, the typical layout is:

• Objects/<builtin>object.c

• Lib/test/test_<builtin>.py

• Doc/library/stdtypes.rst

For builtin functions, the typical layout is:

• Python/bltinmodule.c

• Lib/test/test_<builtin>.py

• Doc/library/functions.rst

Some Exceptions:

• builtin type int is at Objects/longobject.c

• builtin type str is at Objects/unicodeobject.c