Rearranged and added comments to object.h, to clarify many things that have taken me "too long" to reverse-engineer over the years. Vastly reduced the nesting level and redundancy of #ifdef-ery. Took a light stab at repairing comments that are no longer true. sys_gettotalrefcount(): Changed to enable under Py_REF_DEBUG. It was enabled under Py_TRACE_REFS, which was much heavier than necessary. sys.gettotalrefcount() is now available in a Py_REF_DEBUG-only build.