# Protocolo de objeto

PyObject *Py_GetConstant(unsigned int constant_id)
  Parte da ABI Estável desde a versão 3.13.

  Obtém uma referência forte para uma constante.

  Define uma exceção e retorna `NULL` se constant_id for inválido.

  constant_id deve ser um destes identificadores constantes:

  Identificador da constante | Valor | Objeto retornado
  --- | --- | ---
  Py_CONSTANT_NONE | `0` | `None`
  Py_CONSTANT_FALSE | `1` | `False`
  Py_CONSTANT_TRUE | `2` | `True`
  Py_CONSTANT_ELLIPSIS | `3` | `Ellipsis`
  Py_CONSTANT_NOT_IMPLEMENTED | `4` | `NotImplemented`
  Py_CONSTANT_ZERO | `5` | `0`
  Py_CONSTANT_ONE | `6` | `1`
  Py_CONSTANT_EMPTY_STR | `7` | `''`
  Py_CONSTANT_EMPTY_BYTES | `8` | `b''`
  Py_CONSTANT_EMPTY_TUPLE | `9` | `()`

  Valores numéricos são fornecidos apenas para projetos que não podem usar identificadores constantes.

  Adicionado na versão 3.13.

  No CPython, todas essas constantes são imortais.

PyObject *Py_GetConstantBorrowed(unsigned int constant_id)
  Parte da ABI Estável desde a versão 3.13.

  Semelhante a `Py_GetConstant()`, mas retorna uma referência emprestada.

  Esta função destina-se principalmente à compatibilidade com versões anteriores: usar `Py_GetConstant()` é recomendado para novo código.

  A referência é emprestada do interpretador e é válida até a finalização do interpretador.

  Adicionado na versão 3.13.

PyObject *Py_NotImplemented

  O singleton `NotImplemented`, usado para sinalizar que uma operação não foi implementada para a combinação de tipo fornecida.

Py_RETURN_NOTIMPLEMENTED

  Manipula adequadamente o retorno de `Py_NotImplemented` de dentro de uma função C (ou seja, cria uma nova referência forte para `NotImplemented` e retorna-a).

Py_PRINT_RAW

  Sinaliza a ser usado com múltiplas funções que imprimem o objeto (como `PyObject_Print()` e `PyFile_WriteObject()`). Se passada, esta função usaria o `str()` do objeto em vez do `repr()`.

int PyObject_Print(PyObject *o, FILE *fp, int flags)

  Print an object o, on file fp. Returns `-1` on error. The flags argument is used to enable certain printing options. The only option currently supported is `Py_PRINT_RAW`; if given, the `str()` of the object is written instead of the `repr()`.

int PyObject_HasAttrWithError(PyObject *o, PyObject *attr_name)
  Parte da ABI Estável desde a versão 3.13.

  Returns `1` if o has the attribute attr_name, and `0` otherwise. This is equivalent to the Python expression `hasattr(o, attr_name)`. On failure, return `-1`.

  Adicionado na versão 3.13.

int PyObject_HasAttrStringWithError(PyObject *o, const char *attr_name)
  Parte da ABI Estável desde a versão 3.13.

  This is the same as `PyObject_HasAttrWithError()`, but attr_name is specified as a const char* UTF-8 encoded bytes string, rather than a PyObject*.

  Adicionado na versão 3.13.

int PyObject_HasAttr(PyObject *o, PyObject *attr_name)
  Parte da ABI Estável.

  Returns `1` if o has the attribute attr_name, and `0` otherwise. This function always succeeds.

  Nota

  Exceptions that occur when this calls `__getattr__()` and `__getattribute__()` methods aren’t propagated, but instead given to `sys.unraisablehook()`. For proper error handling, use `PyObject_HasAttrWithError()`, `PyObject_GetOptionalAttr()` or `PyObject_GetAttr()` instead.

int PyObject_HasAttrString(PyObject *o, const char *attr_name)
  Parte da ABI Estável.

  This is the same as `PyObject_HasAttr()`, but attr_name is specified as a const char* UTF-8 encoded bytes string, rather than a PyObject*.

  Nota

  Exceptions that occur when this calls `__getattr__()` and `__getattribute__()` methods or while creating the temporary `str` object are silently ignored. For proper error handling, use `PyObject_HasAttrStringWithError()`, `PyObject_GetOptionalAttrString()` or `PyObject_GetAttrString()` instead.

PyObject *PyObject_GetAttr(PyObject *o, PyObject *attr_name)
  Retorna valor: Nova referência. Parte da ABI Estável.

  Retrieve an attribute named attr_name from object o. Returns the attribute value on success, or `NULL` on failure. This is the equivalent of the Python expression `o.attr_name`.

  If the missing attribute should not be treated as a failure, you can use `PyObject_GetOptionalAttr()` instead.

PyObject *PyObject_GetAttrString(PyObject *o, const char *attr_name)
  Retorna valor: Nova referência. Parte da ABI Estável.

  This is the same as `PyObject_GetAttr()`, but attr_name is specified as a const char* UTF-8 encoded bytes string, rather than a PyObject*.

  If the missing attribute should not be treated as a failure, you can use `PyObject_GetOptionalAttrString()` instead.

int PyObject_GetOptionalAttr(PyObject *obj, PyObject *attr_name, PyObject **result);
  Parte da ABI Estável desde a versão 3.13.

  Variant of `PyObject_GetAttr()` which doesn’t raise `AttributeError` if the attribute is not found.

  If the attribute is found, return `1` and set *result to a new strong reference to the attribute. If the attribute is not found, return `0` and set *result to `NULL`; the `AttributeError` is silenced. If an error other than `AttributeError` is raised, return `-1` and set *result to `NULL`.

  Adicionado na versão 3.13.

int PyObject_GetOptionalAttrString(PyObject *obj, const char *attr_name, PyObject **result);
  Parte da ABI Estável desde a versão 3.13.

  This is the same as `PyObject_GetOptionalAttr()`, but attr_name is specified as a const char* UTF-8 encoded bytes string, rather than a PyObject*.

  Adicionado na versão 3.13.

PyObject *PyObject_GenericGetAttr(PyObject *o, PyObject *name)
  Retorna valor: Nova referência. Parte da ABI Estável.

  Generic attribute getter function that is meant to be put into a type object’s `tp_getattro` slot. It looks for a descriptor in the dictionary of classes in the object’s MRO as well as an attribute in the object’s `__dict__` (if present). As outlined in Implementando descritores, data descriptors take preference over instance attributes, while non-data descriptors don’t. Otherwise, an `AttributeError` is raised.

int PyObject_SetAttr(PyObject *o, PyObject *attr_name, PyObject *v)
  Parte da ABI Estável.

  Set the value of the attribute named attr_name, for object o, to the value v. Raise an exception and return `-1` on failure; return `0` on success. This is the equivalent of the Python statement `o.attr_name = v`.

  If v is `NULL`, the attribute is deleted. This behaviour is deprecated in favour of using `PyObject_DelAttr()`, but there are currently no plans to remove it.

int PyObject_SetAttrString(PyObject *o, const char *attr_name, PyObject *v)
  Parte da ABI Estável.

  This is the same as `PyObject_SetAttr()`, but attr_name is specified as a const char* UTF-8 encoded bytes string, rather than a PyObject*.

  If v is `NULL`, the attribute is deleted, but this feature is deprecated in favour of using `PyObject_DelAttrString()`.

  The number of different attribute names passed to this function should be kept small, usually by using a statically allocated string as attr_name. For attribute names that aren’t known at compile time, prefer calling `PyUnicode_FromString()` and `PyObject_SetAttr()` directly. For more details, see `PyUnicode_InternFromString()`, which may be used internally to create a key object.

int PyObject_GenericSetAttr(PyObject *o, PyObject *name, PyObject *value)
  Parte da ABI Estável.

  Generic attribute setter and deleter function that is meant to be put into a type object’s `tp_setattro` slot. It looks for a data descriptor in the dictionary of classes in the object’s MRO, and if found it takes preference over setting or deleting the attribute in the instance dictionary. Otherwise, the attribute is set or deleted in the object’s `__dict__` (if present). On success, `0` is returned, otherwise an `AttributeError` is raised and `-1` is returned.

int PyObject_DelAttr(PyObject *o, PyObject *attr_name)
  Parte da ABI Estável desde a versão 3.13.

  Delete attribute named attr_name, for object o. Returns `-1` on failure. This is the equivalent of the Python statement `del o.attr_name`.

int PyObject_DelAttrString(PyObject *o, const char *attr_name)
  Parte da ABI Estável desde a versão 3.13.

  This is the same as `PyObject_DelAttr()`, but attr_name is specified as a const char* UTF-8 encoded bytes string, rather than a PyObject*.

  The number of different attribute names passed to this function should be kept small, usually by using a statically allocated string as attr_name. For attribute names that aren’t known at compile time, prefer calling `PyUnicode_FromString()` and `PyObject_DelAttr()` directly. For more details, see `PyUnicode_InternFromString()`, which may be used internally to create a key object for lookup.

PyObject *PyObject_GenericGetDict(PyObject *o, void *context)
  Retorna valor: Nova referência. Parte da ABI Estável desde a versão 3.10.

  A generic implementation for the getter of a `__dict__` descriptor. It creates the dictionary if necessary.

  This function may also be called to get the `__dict__` of the object o. Pass `NULL` for context when calling it. Since this function may need to allocate memory for the dictionary, it may be more efficient to call `PyObject_GetAttr()` when accessing an attribute on the object.

  On failure, returns `NULL` with an exception set.

  Adicionado na versão 3.3.

int PyObject_GenericSetDict(PyObject *o, PyObject *value, void *context)
  Parte da ABI Estável desde a versão 3.7.

  A generic implementation for the setter of a `__dict__` descriptor. This implementation does not allow the dictionary to be deleted.

  Adicionado na versão 3.3.

PyObject **_PyObject_GetDictPtr(PyObject *obj)

  Return a pointer to `__dict__` of the object obj. If there is no `__dict__`, return `NULL` without setting an exception.

  This function may need to allocate memory for the dictionary, so it may be more efficient to call `PyObject_GetAttr()` when accessing an attribute on the object.

PyObject *PyObject_RichCompare(PyObject *o1, PyObject *o2, int opid)
  Retorna valor: Nova referência. Parte da ABI Estável.

  Compare the values of o1 and o2 using the operation specified by opid, which must be one of `Py_LT`, `Py_LE`, `Py_EQ`, `Py_NE`, `Py_GT`, or `Py_GE`, corresponding to `<`, `<=`, `==`, `!=`, `>`, or `>=` respectively. This is the equivalent of the Python expression `o1 op o2`, where `op` is the operator corresponding to opid. Returns the value of the comparison on success, or `NULL` on failure.

int PyObject_RichCompareBool(PyObject *o1, PyObject *o2, int opid)
  Parte da ABI Estável.

  Compare the values of o1 and o2 using the operation specified by opid, like `PyObject_RichCompare()`, but returns `-1` on error, `0` if the result is false, `1` otherwise.

Nota

If o1 and o2 are the same object, `PyObject_RichCompareBool()` will always return `1` for `Py_EQ` and `0` for `Py_NE`.

PyObject *PyObject_Format(PyObject *obj, PyObject *format_spec)
  Parte da ABI Estável.

  Format obj using format_spec. This is equivalent to the Python expression `format(obj, format_spec)`.

  format_spec may be `NULL`. In this case the call is equivalent to `format(obj)`. Returns the formatted string on success, `NULL` on failure.

PyObject *PyObject_Repr(PyObject *o)
  Retorna valor: Nova referência. Parte da ABI Estável.

  Compute a string representation of object o. Returns the string representation on success, `NULL` on failure. This is the equivalent of the Python expression `repr(o)`. Called by the `repr()` built-in function.

  Alterado na versão 3.4: Essa função agora inclui uma asserção de depuração para ajudar a garantir que ela não descarte silenciosamente uma exceção ativa.

PyObject *PyObject_ASCII(PyObject *o)
  Retorna valor: Nova referência. Parte da ABI Estável.

  As `PyObject_Repr()`, compute a string representation of object o, but escape the non-ASCII characters in the string returned by `PyObject_Repr()` with `\x`, `\u` or `\U` escapes. This generates a string similar to that returned by `PyObject_Repr()` in Python 2. Called by the `ascii()` built-in function.

PyObject *PyObject_Str(PyObject *o)
  Retorna valor: Nova referência. Parte da ABI Estável.

  Compute a string representation of object o. Returns the string representation on success, `NULL` on failure. This is the equivalent of the Python expression `str(o)`. Called by the `str()` built-in function and, therefore, by the `print()` function.

  Alterado na versão 3.4: Essa função agora inclui uma asserção de depuração para ajudar a garantir que ela não descarte silenciosamente uma exceção ativa.

PyObject *PyObject_Bytes(PyObject *o)
  Retorna valor: Nova referência. Parte da ABI Estável.

  Compute a bytes representation of object o. `NULL` is returned on failure and a bytes object on success. This is equivalent to the Python expression `bytes(o)`, when o is not an integer. Unlike `bytes(o)`, a TypeError is raised when o is an integer instead of a zero-initialized bytes object.

int PyObject_IsSubclass(PyObject *derived, PyObject *cls)
  Parte da ABI Estável.

  Return `1` if the class derived is identical to or derived from the class cls, otherwise return `0`. In case of an error, return `-1`.

  If cls is a tuple, the check will be done against every entry in cls. The result will be `1` when at least one of the checks returns `1`, otherwise it will be `0`.

  If cls has a `__subclasscheck__()` method, it will be called to determine the subclass status as described in PEP 3119. Otherwise, derived is a subclass of cls if it is a direct or indirect subclass, i.e. contained in `cls.__mro__`.

  Normally only class objects, i.e. instances of `type` or a derived class, are considered classes. However, objects can override this by having a `__bases__` attribute (which must be a tuple of base classes).

int PyObject_IsInstance(PyObject *inst, PyObject *cls)
  Parte da ABI Estável.

  Return `1` if inst is an instance of the class cls or a subclass of cls, or `0` if not. On error, returns `-1` and sets an exception.

  If cls is a tuple, the check will be done against every entry in cls. The result will be `1` when at least one of the checks returns `1`, otherwise it will be `0`.

  If cls has a `__instancecheck__()` method, it will be called to determine the subclass status as described in PEP 3119. Otherwise, inst is an instance of cls if its class is a subclass of cls.

  An instance inst can override what is considered its class by having a `__class__` attribute.

  An object cls can override if it is considered a class, and what its base classes are, by having a `__bases__` attribute (which must be a tuple of base classes).

Py_hash_t PyObject_Hash(PyObject *o)
  Parte da ABI Estável.

  Compute and return the hash value of an object o. On failure, return `-1`. This is the equivalent of the Python expression `hash(o)`.

  Alterado na versão 3.2: The return type is now Py_hash_t. This is a signed integer the same size as `Py_ssize_t`.

Py_hash_t PyObject_HashNotImplemented(PyObject *o)
  Parte da ABI Estável.

  Set a `TypeError` indicating that `type(o)` is not hashable and return `-1`. This function receives special treatment when stored in a `tp_hash` slot, allowing a type to explicitly indicate to the interpreter that it is not hashable.

int PyObject_IsTrue(PyObject *o)
  Parte da ABI Estável.

  Returns `1` if the object o is considered to be true, and `0` otherwise. This is equivalent to the Python expression `not not o`. On failure, return `-1`.

int PyObject_Not(PyObject *o)
  Parte da ABI Estável.

  Returns `0` if the object o is considered to be true, and `1` otherwise. This is equivalent to the Python expression `not o`. On failure, return `-1`.

PyObject *PyObject_Type(PyObject *o)
  Retorna valor: Nova referência. Parte da ABI Estável.

  When o is non-`NULL`, returns a type object corresponding to the object type of object o. On failure, raises `SystemError` and returns `NULL`. This is equivalent to the Python expression `type(o)`. This function creates a new strong reference to the return value. There’s really no reason to use this function instead of the `Py_TYPE()` function, which returns a pointer of type PyTypeObject*, except when a new strong reference is needed.

int PyObject_TypeCheck(PyObject *o, PyTypeObject *type)

  Return non-zero if the object o is of type type or a subtype of type, and `0` otherwise. Both parameters must be non-`NULL`.

Py_ssize_t PyObject_Size(PyObject *o)
Py_ssize_t PyObject_Length(PyObject *o)
  Parte da ABI Estável.

  Return the length of object o. If the object o provides either the sequence and mapping protocols, the sequence length is returned. On error, `-1` is returned. This is the equivalent to the Python expression `len(o)`.

Py_ssize_t PyObject_LengthHint(PyObject *o, Py_ssize_t defaultvalue)

  Return an estimated length for the object o. First try to return its actual length, then an estimate using `__length_hint__()`, and finally return the default value. On error return `-1`. This is the equivalent to the Python expression `operator.length_hint(o, defaultvalue)`.

  Adicionado na versão 3.4.

PyObject *PyObject_GetItem(PyObject *o, PyObject *key)
  Retorna valor: Nova referência. Parte da ABI Estável.

  Return element of o corresponding to the object key or `NULL` on failure. This is the equivalent of the Python expression `o[key]`.

int PyObject_SetItem(PyObject *o, PyObject *key, PyObject *v)
  Parte da ABI Estável.

  Map the object key to the value v. Raise an exception and return `-1` on failure; return `0` on success. This is the equivalent of the Python statement `o[key] = v`. This function does not steal a reference to v.

int PyObject_DelItem(PyObject *o, PyObject *key)
  Parte da ABI Estável.

  Remove the mapping for the object key from the object o. Return `-1` on failure. This is equivalent to the Python statement `del o[key]`.

int PyObject_DelItemString(PyObject *o, const char *key)
  Parte da ABI Estável.

  É o mesmo que `PyObject_DelItem()`, mas key é especificada como uma string de bytes const char* codificada em UTF-8, em vez de um PyObject*.

PyObject *PyObject_Dir(PyObject *o)
  Retorna valor: Nova referência. Parte da ABI Estável.

  This is equivalent to the Python expression `dir(o)`, returning a (possibly empty) list of strings appropriate for the object argument, or `NULL` if there was an error. If the argument is `NULL`, this is like the Python `dir()`, returning the names of the current locals; in this case, if no execution frame is active then `NULL` is returned but `PyErr_Occurred()` will return false.

PyObject *PyObject_GetIter(PyObject *o)
  Retorna valor: Nova referência. Parte da ABI Estável.

  This is equivalent to the Python expression `iter(o)`. It returns a new iterator for the object argument, or the object itself if the object is already an iterator. Raises `TypeError` and returns `NULL` if the object cannot be iterated.

PyObject *PyObject_SelfIter(PyObject *obj)
  Retorna valor: Nova referência. Parte da ABI Estável.

  This is equivalent to the Python `__iter__(self): return self` method. It is intended for iterator types, to be used in the `PyTypeObject.tp_iter` slot.

PyObject *PyObject_GetAIter(PyObject *o)
  Retorna valor: Nova referência. Parte da ABI Estável desde a versão 3.10.

  This is the equivalent to the Python expression `aiter(o)`. Takes an `AsyncIterable` object and returns an `AsyncIterator` for it. This is typically a new iterator but if the argument is an `AsyncIterator`, this returns itself. Raises `TypeError` and returns `NULL` if the object cannot be iterated.

  Adicionado na versão 3.10.

void *PyObject_GetTypeData(PyObject *o, PyTypeObject *cls)
  Parte da ABI Estável desde a versão 3.12.

  Get a pointer to subclass-specific data reserved for cls.

  The object o must be an instance of cls, and cls must have been created using negative `PyType_Spec.basicsize`. Python does not check this.

  On error, set an exception and return `NULL`.

  Adicionado na versão 3.12.

Py_ssize_t PyType_GetTypeDataSize(PyTypeObject *cls)
  Parte da ABI Estável desde a versão 3.12.

  Return the size of the instance memory space reserved for cls, i.e. the size of the memory `PyObject_GetTypeData()` returns.

  This may be larger than requested using `-PyType_Spec.basicsize`; it is safe to use this larger size (e.g. with `memset()`).

  The type cls must have been created using negative `PyType_Spec.basicsize`. Python does not check this.

  On error, set an exception and return a negative value.

  Adicionado na versão 3.12.

void *PyObject_GetItemData(PyObject *o)

  Get a pointer to per-item data for a class with `Py_TPFLAGS_ITEMS_AT_END`.

  On error, set an exception and return `NULL`. `TypeError` is raised if o does not have `Py_TPFLAGS_ITEMS_AT_END` set.

  Adicionado na versão 3.12.

int PyObject_VisitManagedDict(PyObject *obj, visitproc visit, void *arg)

  Visit the managed dictionary of obj.

  This function must only be called in a traverse function of the type which has the `Py_TPFLAGS_MANAGED_DICT` flag set.

  Adicionado na versão 3.13.

void PyObject_ClearManagedDict(PyObject *obj)

  Clear the managed dictionary of obj.

  This function must only be called in a clear function of the type which has the `Py_TPFLAGS_MANAGED_DICT` flag set.

  Adicionado na versão 3.13.

int PyUnstable_Object_EnableDeferredRefcount(PyObject *obj)
  Esta é uma API Instável. Isso pode se alterado sem aviso em lançamentos menores.

  Enable deferred reference counting on obj, if supported by the runtime. In the free-threaded build, this allows the interpreter to avoid reference count adjustments to obj, which may improve multi-threaded performance. The tradeoff is that obj will only be deallocated by the tracing garbage collector, and not when the interpreter no longer has any references to it.

  This function returns `1` if deferred reference counting is enabled on obj, and `0` if deferred reference counting is not supported or if the hint was ignored by the interpreter, such as when deferred reference counting is already enabled on obj. This function is thread-safe, and cannot fail.

  This function does nothing on builds with the GIL enabled, which do not support deferred reference counting. This also does nothing if obj is not an object tracked by the garbage collector (see `gc.is_tracked()` and `PyObject_GC_IsTracked()`).

  This function is intended to be used soon after obj is created, by the code that creates it, such as in the object’s `tp_new` slot.

  Adicionado na versão 3.14.

int PyUnstable_Object_IsUniqueReferencedTemporary(PyObject *obj)
  Esta é uma API Instável. Isso pode se alterado sem aviso em lançamentos menores.

  Check if obj is a unique temporary object. Returns `1` if obj is known to be a unique temporary object, and `0` otherwise. This function cannot fail, but the check is conservative, and may return `0` in some cases even if obj is a unique temporary object.

  If an object is a unique temporary, it is guaranteed that the current code has the only reference to the object. For arguments to C functions, this should be used instead of checking if the reference count is `1`. Starting with Python 3.14, the interpreter internally avoids some reference count modifications when loading objects onto the operands stack by borrowing references when possible, which means that a reference count of `1` by itself does not guarantee that a function argument uniquely referenced.

  In the example below, `my_func` is called with a unique temporary object as its argument:

      my_func([1, 2, 3])

  In the example below, `my_func` is not called with a unique temporary object as its argument, even if its refcount is `1`:

      my_list = [1, 2, 3]
      my_func(my_list)

  See also the function `Py_REFCNT()`.

  Adicionado na versão 3.14.

int PyUnstable_IsImmortal(PyObject *obj)
  Esta é uma API Instável. Isso pode se alterado sem aviso em lançamentos menores.

  Essa função retorna um valor diferente de zero se obj for immortal, e zero caso contrário. Essa função nunca falha.

  Nota

  Objetos que são imortais em um versão do CPython não têm garantia de ser imortal em outro.

  Adicionado na versão 3.14.

int PyUnstable_TryIncRef(PyObject *obj)
  Esta é uma API Instável. Isso pode se alterado sem aviso em lançamentos menores.

  Increments the reference count of obj if it is not zero. Returns `1` if the object’s reference count was successfully incremented. Otherwise, this function returns `0`.

  `PyUnstable_EnableTryIncRef()` must have been called earlier on obj or this function may spuriously return `0` in the free threading build.

  This function is logically equivalent to the following C code, except that it behaves atomically in the free threading build:

      if (Py_REFCNT(op) > 0) {
         Py_INCREF(op);
         return 1;
      }
      return 0;

  This is intended as a building block for managing weak references without the overhead of a Python weak reference object.

  Typically, correct use of this function requires support from obj’s deallocator (`tp_dealloc`). For example, the following sketch could be adapted to implement a “weakmap” that works like a `WeakValueDictionary` for a specific type:

      PyMutex mutex;

      PyObject *
      add_entry(weakmap_key_type *key, PyObject *value)
      {
          PyUnstable_EnableTryIncRef(value);
          weakmap_type weakmap = ...;
          PyMutex_Lock(&mutex);
          weakmap_add_entry(weakmap, key, value);
          PyMutex_Unlock(&mutex);
          Py_RETURN_NONE;
      }

      PyObject *
      get_value(weakmap_key_type *key)
      {
          weakmap_type weakmap = ...;
          PyMutex_Lock(&mutex);
          PyObject *result = weakmap_find(weakmap, key);
          if (PyUnstable_TryIncRef(result)) {
              // `result` is safe to use
              PyMutex_Unlock(&mutex);
              return result;
          }
          // if we get here, `result` is starting to be garbage-collected,
          // but has not been removed from the weakmap yet
          PyMutex_Unlock(&mutex);
          return NULL;
      }

      // tp_dealloc function for weakmap values
      void
      value_dealloc(PyObject *value)
      {
          weakmap_type weakmap = ...;
          PyMutex_Lock(&mutex);
          weakmap_remove_value(weakmap, value);

          ...
          PyMutex_Unlock(&mutex);
      }

  Adicionado na versão 3.14.

void PyUnstable_EnableTryIncRef(PyObject *obj)
  Esta é uma API Instável. Isso pode se alterado sem aviso em lançamentos menores.

  Enables subsequent uses of `PyUnstable_TryIncRef()` on obj. The caller must hold a strong reference to obj when calling this.

  Adicionado na versão 3.14.

int PyUnstable_Object_IsUniquelyReferenced(PyObject *op)
  Esta é uma API Instável. Isso pode se alterado sem aviso em lançamentos menores.

  Determine if op only has one reference.

  On GIL-enabled builds, this function is equivalent to Py_REFCNT(op) == 1.

  On a free threaded build, this checks if op’s reference count is equal to one and additionally checks if op is only used by this thread. Py_REFCNT(op) == 1 is not thread-safe on free threaded builds; prefer this function.

  The caller must hold an attached thread state, despite the fact that this function doesn’t call into the Python interpreter. This function cannot fail.

  Adicionado na versão 3.14.