Coverage Report

Created: 2022-07-08 09:39

/home/mdboom/Work/builds/cpython/Include/objimpl.h
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/* The PyObject_ memory family:  high-level object memory interfaces.
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   See pymem.h for the low-level PyMem_ family.
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*/
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#ifndef Py_OBJIMPL_H
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#define Py_OBJIMPL_H
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#include "pymem.h"
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#ifdef __cplusplus
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extern "C" {
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#endif
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/* BEWARE:
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   Each interface exports both functions and macros.  Extension modules should
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   use the functions, to ensure binary compatibility across Python versions.
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   Because the Python implementation is free to change internal details, and
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   the macros may (or may not) expose details for speed, if you do use the
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   macros you must recompile your extensions with each Python release.
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   Never mix calls to PyObject_ memory functions with calls to the platform
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   malloc/realloc/ calloc/free, or with calls to PyMem_.
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*/
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/*
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Functions and macros for modules that implement new object types.
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 - PyObject_New(type, typeobj) allocates memory for a new object of the given
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   type, and initializes part of it.  'type' must be the C structure type used
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   to represent the object, and 'typeobj' the address of the corresponding
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   type object.  Reference count and type pointer are filled in; the rest of
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   the bytes of the object are *undefined*!  The resulting expression type is
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   'type *'.  The size of the object is determined by the tp_basicsize field
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   of the type object.
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 - PyObject_NewVar(type, typeobj, n) is similar but allocates a variable-size
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   object with room for n items.  In addition to the refcount and type pointer
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   fields, this also fills in the ob_size field.
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 - PyObject_Free(op) releases the memory allocated for an object.  It does not
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   run a destructor -- it only frees the memory.  PyObject_Free is identical.
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 - PyObject_Init(op, typeobj) and PyObject_InitVar(op, typeobj, n) don't
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   allocate memory.  Instead of a 'type' parameter, they take a pointer to a
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   new object (allocated by an arbitrary allocator), and initialize its object
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   header fields.
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Note that objects created with PyObject_{New, NewVar} are allocated using the
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specialized Python allocator (implemented in obmalloc.c), if WITH_PYMALLOC is
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enabled.  In addition, a special debugging allocator is used if Py_DEBUG
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macro is also defined.
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In case a specific form of memory management is needed (for example, if you
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must use the platform malloc heap(s), or shared memory, or C++ local storage or
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operator new), you must first allocate the object with your custom allocator,
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then pass its pointer to PyObject_{Init, InitVar} for filling in its Python-
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specific fields:  reference count, type pointer, possibly others.  You should
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be aware that Python has no control over these objects because they don't
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cooperate with the Python memory manager.  Such objects may not be eligible
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for automatic garbage collection and you have to make sure that they are
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released accordingly whenever their destructor gets called (cf. the specific
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form of memory management you're using).
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Unless you have specific memory management requirements, use
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PyObject_{New, NewVar, Del}.
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*/
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/*
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 * Raw object memory interface
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 * ===========================
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 */
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/* Functions to call the same malloc/realloc/free as used by Python's
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   object allocator.  If WITH_PYMALLOC is enabled, these may differ from
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   the platform malloc/realloc/free.  The Python object allocator is
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   designed for fast, cache-conscious allocation of many "small" objects,
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   and with low hidden memory overhead.
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   PyObject_Malloc(0) returns a unique non-NULL pointer if possible.
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   PyObject_Realloc(NULL, n) acts like PyObject_Malloc(n).
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   PyObject_Realloc(p != NULL, 0) does not return  NULL, or free the memory
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   at p.
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   Returned pointers must be checked for NULL explicitly; no action is
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   performed on failure other than to return NULL (no warning it printed, no
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   exception is set, etc).
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   For allocating objects, use PyObject_{New, NewVar} instead whenever
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   possible.  The PyObject_{Malloc, Realloc, Free} family is exposed
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   so that you can exploit Python's small-block allocator for non-object
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   uses.  If you must use these routines to allocate object memory, make sure
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   the object gets initialized via PyObject_{Init, InitVar} after obtaining
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   the raw memory.
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*/
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PyAPI_FUNC(void *) PyObject_Malloc(size_t size);
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#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03050000
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PyAPI_FUNC(void *) PyObject_Calloc(size_t nelem, size_t elsize);
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#endif
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PyAPI_FUNC(void *) PyObject_Realloc(void *ptr, size_t new_size);
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PyAPI_FUNC(void) PyObject_Free(void *ptr);
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// Deprecated aliases only kept for backward compatibility.
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// PyObject_Del and PyObject_DEL are defined with no parameter to be able to
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// use them as function pointers (ex: tp_free = PyObject_Del).
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#define PyObject_MALLOC         PyObject_Malloc
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#define PyObject_REALLOC        PyObject_Realloc
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#define PyObject_FREE           PyObject_Free
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#define PyObject_Del            PyObject_Free
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#define PyObject_DEL            PyObject_Free
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/*
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 * Generic object allocator interface
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 * ==================================
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 */
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/* Functions */
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PyAPI_FUNC(PyObject *) PyObject_Init(PyObject *, PyTypeObject *);
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PyAPI_FUNC(PyVarObject *) PyObject_InitVar(PyVarObject *,
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                                           PyTypeObject *, Py_ssize_t);
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#define PyObject_INIT(op, typeobj) \
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    PyObject_Init(_PyObject_CAST(op), (typeobj))
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#define PyObject_INIT_VAR(op, typeobj, size) \
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    PyObject_InitVar(_PyVarObject_CAST(op), (typeobj), (size))
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PyAPI_FUNC(PyObject *) _PyObject_New(PyTypeObject *);
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PyAPI_FUNC(PyVarObject *) _PyObject_NewVar(PyTypeObject *, Py_ssize_t);
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#define PyObject_New(type, typeobj) ((type *)_PyObject_New(typeobj))
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// Alias to PyObject_New(). In Python 3.8, PyObject_NEW() called directly
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// PyObject_MALLOC() with _PyObject_SIZE().
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#define PyObject_NEW(type, typeobj) PyObject_New(type, (typeobj))
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#define PyObject_NewVar(type, typeobj, n) \
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                ( (type *) _PyObject_NewVar((typeobj), (n)) )
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// Alias to PyObject_NewVar(). In Python 3.8, PyObject_NEW_VAR() called
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// directly PyObject_MALLOC() with _PyObject_VAR_SIZE().
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#define PyObject_NEW_VAR(type, typeobj, n) PyObject_NewVar(type, (typeobj), (n))
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/*
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 * Garbage Collection Support
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 * ==========================
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 */
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/* C equivalent of gc.collect(). */
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PyAPI_FUNC(Py_ssize_t) PyGC_Collect(void);
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/* C API for controlling the state of the garbage collector */
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PyAPI_FUNC(int) PyGC_Enable(void);
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PyAPI_FUNC(int) PyGC_Disable(void);
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PyAPI_FUNC(int) PyGC_IsEnabled(void);
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/* Test if a type has a GC head */
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#define PyType_IS_GC(t) PyType_HasFeature((t), 
Py_TPFLAGS_HAVE_GC19.9G
)
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PyAPI_FUNC(PyVarObject *) _PyObject_GC_Resize(PyVarObject *, Py_ssize_t);
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#define PyObject_GC_Resize(type, op, n) \
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                ( (type *) _PyObject_GC_Resize(_PyVarObject_CAST(op), (n)) )
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PyAPI_FUNC(PyObject *) _PyObject_GC_New(PyTypeObject *);
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PyAPI_FUNC(PyVarObject *) _PyObject_GC_NewVar(PyTypeObject *, Py_ssize_t);
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/* Tell the GC to track this object.
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 *
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 * See also private _PyObject_GC_TRACK() macro. */
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PyAPI_FUNC(void) PyObject_GC_Track(void *);
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/* Tell the GC to stop tracking this object.
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 *
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 * See also private _PyObject_GC_UNTRACK() macro. */
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PyAPI_FUNC(void) PyObject_GC_UnTrack(void *);
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PyAPI_FUNC(void) PyObject_GC_Del(void *);
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#define PyObject_GC_New(type, typeobj) \
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    _Py_CAST(type*, _PyObject_GC_New(typeobj))
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#define PyObject_GC_NewVar(type, typeobj, n) \
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    _Py_CAST(type*, _PyObject_GC_NewVar((typeobj), (n)))
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PyAPI_FUNC(int) PyObject_GC_IsTracked(PyObject *);
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PyAPI_FUNC(int) PyObject_GC_IsFinalized(PyObject *);
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/* Utility macro to help write tp_traverse functions.
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 * To use this macro, the tp_traverse function must name its arguments
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 * "visit" and "arg".  This is intended to keep tp_traverse functions
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 * looking as much alike as possible.
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 */
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#define Py_VISIT(op)                                                    \
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    do {                                                                \
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        if (op) {                                                       \
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            int vret = visit(_PyObject_CAST(op), arg);                  \
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            if (vret)                                                   \
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return vret805
; \
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        }                                                               \
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    } while (
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)
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#ifndef Py_LIMITED_API
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#  define Py_CPYTHON_OBJIMPL_H
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#  include "cpython/objimpl.h"
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#  undef Py_CPYTHON_OBJIMPL_H
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#endif
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#ifdef __cplusplus
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}
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#endif
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#endif /* !Py_OBJIMPL_H */