Add use_weakref option to functools.lru_cache The use_weakref option makes lru_cache create weak references to the function arguments when creating the cache key, which prevents them from staying in the memory forever even after all other references to them are gone. This is a proof of concept for http://bugs.python.org/issue19859

#ifndef Py_METAGRAMMAR_H
#define Py_METAGRAMMAR_H
#ifdef __cplusplus
extern "C" {
#endif


#define MSTART 256
#define RULE 257
#define RHS 258
#define ALT 259
#define ITEM 260
#define ATOM 261

#ifdef __cplusplus
}
#endif
#endif /* !Py_METAGRAMMAR_H */