python object 对象定义之精

python object 对象定义之精
#ifdef Py_TRACE_REFS
/* Define pointers to support a doubly-linked list of all live heap objects. */
#define _PyObject_HEAD_EXTRA        /
    struct _object *_ob_next;    /
    struct _object *_ob_prev;

#define _PyObject_EXTRA_INIT 0, 0,

#else
#define _PyObject_HEAD_EXTRA
#define _PyObject_EXTRA_INIT
#endif