Python 3.6.5 Documentation >  Allocating Objects on the Heap

Allocating Objects on the Heap
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PyObject* _PyObject_New(PyTypeObject *type)
*Return value: New reference.*

PyVarObject* _PyObject_NewVar(PyTypeObject *type, Py_ssize_t size)
*Return value: New reference.*

PyObject* PyObject_Init(PyObject *op, PyTypeObject *type)
*Return value: Borrowed reference.*

Initialize a newly-allocated object *op* with its type and initial
reference. Returns the initialized object. If *type* indicates
that the object participates in the cyclic garbage detector, it is
added to the detector’s set of observed objects. Other fields of
the object are not affected.

PyVarObject* PyObject_InitVar(PyVarObject *op, PyTypeObject *type, Py_ssize_t size)
*Return value: Borrowed reference.*

This does everything "PyObject_Init()" does, and also initializes
the length information for a variable-size object.

TYPE* PyObject_New(TYPE, PyTypeObject *type)
*Return value: New reference.*

Allocate a new Python object using the C structure type *TYPE* and
the Python type object *type*. Fields not defined by the Python
object header are not initialized; the object’s reference count
will be one. The size of the memory allocation is determined from
the "tp_basicsize" field of the type object.

TYPE* PyObject_NewVar(TYPE, PyTypeObject *type, Py_ssize_t size)
*Return value: New reference.*

Allocate a new Python object using the C structure type *TYPE* and
the Python type object *type*. Fields not defined by the Python
object header are not initialized. The allocated memory allows for
the *TYPE* structure plus *size* fields of the size given by the
"tp_itemsize" field of *type*. 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.

void PyObject_Del(PyObject *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

Object which is visible in Python as "None". This should only be
accessed using the "Py_None" macro, which evaluates to a pointer to
this object.

See also:

"PyModule_Create()"
To allocate and create extension modules.