Object Protocol

PyObject *Py_GetConstant(unsigned int constant_id)
Part of the Stable ABI since version 3.13.

Get a strong reference to a constant.

Set an exception and return NULL if constant_id is invalid.

constant_id must be one of these constant identifiers:

Constant Identifier

Value

Returned object

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

()

Numeric values are only given for projects which cannot use the constant identifiers.

Added in version 3.13.

CPython implementation detail: In CPython, all of these constants are immortal.

PyObject *Py_GetConstantBorrowed(unsigned int constant_id)
Part of the Stable ABI since version 3.13.

Similar to Py_GetConstant(), but return a borrowed reference.

This function is primarily intended for backwards compatibility: using Py_GetConstant() is recommended for new code.

The reference is borrowed from the interpreter, and is valid until the interpreter finalization.

Added in version 3.13.

PyObject *Py_NotImplemented

The NotImplemented singleton, used to signal that an operation is not implemented for the given type combination.

Py_RETURN_NOTIMPLEMENTED

Properly handle returning Py_NotImplemented from within a C function (that is, create a new strong reference to NotImplemented and return it).

Py_PRINT_RAW

Flag to be used with multiple functions that print the object (like PyObject_Print() and PyFile_WriteObject()). If passed, these functions use the str() of the object instead of the