オブジェクトをヒープ上にメモリ確保する
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PyObject *_PyObject_New(PyTypeObject *type)
    *戻り値: 新しい参照。*

PyVarObject *_PyObject_NewVar(PyTypeObject *type, Py_ssize_t size)
    *戻り値: 新しい参照。*

PyObject *PyObject_Init(PyObject *op, PyTypeObject *type)
    *戻り値: 借用参照。** 次に属します: Stable ABI.*

   Initialize a newly allocated object *op* with its type and initial
   reference.  Returns the initialized object.  Other fields of the
   object are not affected.

PyVarObject *PyObject_InitVar(PyVarObject *op, PyTypeObject *type, Py_ssize_t size)
    *戻り値: 借用参照。** 次に属します: Stable ABI.*

   "PyObject_Init()" の全ての処理を行い、可変サイズオブジェクトの場合
   には長さ情報も初期化します。

PyObject_New(TYPE, typeobj)

   Allocate a new Python object using the C structure type *TYPE* and
   the Python type object *typeobj* ("PyTypeObject*"). Fields not
   defined by the Python object header are not initialized. The caller
   will own the only reference to the object (i.e. its reference count
   will be one). The size of the memory allocation is determined from
   the "tp_basicsize" field of the type object.

   Note that this function is unsuitable if *typeobj* has
   "Py_TPFLAGS_HAVE_GC" set. For such objects, use "PyObject_GC_New()"
   instead.

PyObject_NewVar(TYPE, typeobj, size)

   Allocate a new Python object using the C structure type *TYPE* and
   the Python type object *typeobj* ("PyTypeObject*"). Fields not
   defined by the Python object header are not initialized.  The
   allocated memory allows for the *TYPE* structure plus *size*
   ("Py_ssize_t") fields of the size given by the "tp_itemsize" field
   of *typeobj*.  This is useful for implementing objects like tuples,
   which are able to determine their size at construction time.
   Embedding the array of fields into the same allocation decreases
   the number of allocations, improving the memory management
   efficiency.

   Note that this function is unsuitable if *typeobj* has
   "Py_TPFLAGS_HAVE_GC" set. For such objects, use
   "PyObject_GC_NewVar()" instead.

void PyObject_Del(void *op)

   Releases memory allocated to an object using "PyObject_New" or
   "PyObject_NewVar".  This is normally called from the "tp_dealloc"
   handler specified in the object's type.  The fields of the object
   should not be accessed after this call as the memory is no longer a
   valid Python object.

PyObject _Py_NoneStruct

   Python からは "None" に見えるオブジェクトです。この値へのアクセスは
   、このオブジェクトへのポインタを評価する "Py_None" マクロを使わなけ
   ればなりません。

参考:

  "PyModule_Create()"
     拡張モジュールのアロケートと生成。
