cpython/Include/cpython/dictobject.h

#ifndef Py_CPYTHON_DICTOBJECT_H
#  error "this header file must not be included directly"
#endif

PyDictKeysObject;
PyDictValues;

/* The ma_values pointer is NULL for a combined table
 * or points to an array of PyObject* for a split table
 */
PyDictObject;

PyAPI_FUNC(PyObject *) _PyDict_GetItem_KnownHash(PyObject *mp, PyObject *key,
                                                 Py_hash_t hash);
// PyDict_GetItemStringRef() can be used instead
Py_DEPRECATED(3.14) PyAPI_FUNC(PyObject *) _PyDict_GetItemStringWithError(PyObject *, const char *);
PyAPI_FUNC(PyObject *) PyDict_SetDefault(
    PyObject *mp, PyObject *key, PyObject *defaultobj);

// Inserts `key` with a value `default_value`, if `key` is not already present
// in the dictionary.  If `result` is not NULL, then the value associated
// with `key` is returned in `*result` (either the existing value, or the now
// inserted `default_value`).
// Returns:
//   -1 on error
//    0 if `key` was not present and `default_value` was inserted
//    1 if `key` was present and `default_value` was not inserted
PyAPI_FUNC(int) PyDict_SetDefaultRef(PyObject *mp, PyObject *key, PyObject *default_value, PyObject **result);

/* Get the number of items of a dictionary. */
static inline Py_ssize_t PyDict_GET_SIZE(PyObject *op) { … }
#define PyDict_GET_SIZE(op) …

PyAPI_FUNC(int) PyDict_ContainsString(PyObject *mp, const char *key);

PyAPI_FUNC(PyObject *) _PyDict_NewPresized(Py_ssize_t minused);

PyAPI_FUNC(int) PyDict_Pop(PyObject *dict, PyObject *key, PyObject **result);
PyAPI_FUNC(int) PyDict_PopString(PyObject *dict, const char *key, PyObject **result);
PyAPI_FUNC(PyObject *) _PyDict_Pop(PyObject *dict, PyObject *key, PyObject *default_value);

/* Dictionary watchers */

#define PY_FOREACH_DICT_EVENT(V) …

PyDict_WatchEvent;

// Callback to be invoked when a watched dict is cleared, dealloced, or modified.
// In clear/dealloc case, key and new_value will be NULL. Otherwise, new_value will be the
// new value for key, NULL if key is being deleted.
PyDict_WatchCallback;

// Register/unregister a dict-watcher callback
PyAPI_FUNC(int) PyDict_AddWatcher(PyDict_WatchCallback callback);
PyAPI_FUNC(int) PyDict_ClearWatcher(int watcher_id);

// Mark given dictionary as "watched" (callback will be called if it is modified)
PyAPI_FUNC(int) PyDict_Watch(int watcher_id, PyObject* dict);
PyAPI_FUNC(int) PyDict_Unwatch(int watcher_id, PyObject* dict);