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_PGEN_H
#define Py_PGEN_H
#ifdef __cplusplus
extern "C" {
#endif


/* Parser generator interface */

extern grammar *meta_grammar(void);

struct _node;
extern grammar *pgen(struct _node *);

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