--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/CSP2/CSP2_env/env-d9b9114564458d9d-741b3de822f2aaca6c6caa4325c4afce/include/python3.8/object.h	Tue Mar 18 17:55:14 2025 -0400
@@ -0,0 +1,753 @@
+#ifndef Py_OBJECT_H
+#define Py_OBJECT_H
+
+#include "pymem.h"   /* _Py_tracemalloc_config */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+/* Object and type object interface */
+
+/*
+Objects are structures allocated on the heap.  Special rules apply to
+the use of objects to ensure they are properly garbage-collected.
+Objects are never allocated statically or on the stack; they must be
+accessed through special macros and functions only.  (Type objects are
+exceptions to the first rule; the standard types are represented by
+statically initialized type objects, although work on type/class unification
+for Python 2.2 made it possible to have heap-allocated type objects too).
+
+An object has a 'reference count' that is increased or decreased when a
+pointer to the object is copied or deleted; when the reference count
+reaches zero there are no references to the object left and it can be
+removed from the heap.
+
+An object has a 'type' that determines what it represents and what kind
+of data it contains.  An object's type is fixed when it is created.
+Types themselves are represented as objects; an object contains a
+pointer to the corresponding type object.  The type itself has a type
+pointer pointing to the object representing the type 'type', which
+contains a pointer to itself!).
+
+Objects do not float around in memory; once allocated an object keeps
+the same size and address.  Objects that must hold variable-size data
+can contain pointers to variable-size parts of the object.  Not all
+objects of the same type have the same size; but the size cannot change
+after allocation.  (These restrictions are made so a reference to an
+object can be simply a pointer -- moving an object would require
+updating all the pointers, and changing an object's size would require
+moving it if there was another object right next to it.)
+
+Objects are always accessed through pointers of the type 'PyObject *'.
+The type 'PyObject' is a structure that only contains the reference count
+and the type pointer.  The actual memory allocated for an object
+contains other data that can only be accessed after casting the pointer
+to a pointer to a longer structure type.  This longer type must start
+with the reference count and type fields; the macro PyObject_HEAD should be
+used for this (to accommodate for future changes).  The implementation
+of a particular object type can cast the object pointer to the proper
+type and back.
+
+A standard interface exists for objects that contain an array of items
+whose size is determined when the object is allocated.
+*/
+
+/* Py_DEBUG implies Py_REF_DEBUG. */
+#if defined(Py_DEBUG) && !defined(Py_REF_DEBUG)
+#define Py_REF_DEBUG
+#endif
+
+#if defined(Py_LIMITED_API) && defined(Py_REF_DEBUG)
+#error Py_LIMITED_API is incompatible with Py_DEBUG, Py_TRACE_REFS, and Py_REF_DEBUG
+#endif
+
+
+#ifdef Py_TRACE_REFS
+/* Define pointers to support a doubly-linked list of all live heap objects. */
+#define _PyObject_HEAD_EXTRA            \
+    struct _object *_ob_next;           \
+    struct _object *_ob_prev;
+
+#define _PyObject_EXTRA_INIT 0, 0,
+
+#else
+#define _PyObject_HEAD_EXTRA
+#define _PyObject_EXTRA_INIT
+#endif
+
+/* PyObject_HEAD defines the initial segment of every PyObject. */
+#define PyObject_HEAD                   PyObject ob_base;
+
+#define PyObject_HEAD_INIT(type)        \
+    { _PyObject_EXTRA_INIT              \
+    1, type },
+
+#define PyVarObject_HEAD_INIT(type, size)       \
+    { PyObject_HEAD_INIT(type) size },
+
+/* PyObject_VAR_HEAD defines the initial segment of all variable-size
+ * container objects.  These end with a declaration of an array with 1
+ * element, but enough space is malloc'ed so that the array actually
+ * has room for ob_size elements.  Note that ob_size is an element count,
+ * not necessarily a byte count.
+ */
+#define PyObject_VAR_HEAD      PyVarObject ob_base;
+#define Py_INVALID_SIZE (Py_ssize_t)-1
+
+/* Nothing is actually declared to be a PyObject, but every pointer to
+ * a Python object can be cast to a PyObject*.  This is inheritance built
+ * by hand.  Similarly every pointer to a variable-size Python object can,
+ * in addition, be cast to PyVarObject*.
+ */
+typedef struct _object {
+    _PyObject_HEAD_EXTRA
+    Py_ssize_t ob_refcnt;
+    struct _typeobject *ob_type;
+} PyObject;
+
+/* Cast argument to PyObject* type. */
+#define _PyObject_CAST(op) ((PyObject*)(op))
+
+typedef struct {
+    PyObject ob_base;
+    Py_ssize_t ob_size; /* Number of items in variable part */
+} PyVarObject;
+
+/* Cast argument to PyVarObject* type. */
+#define _PyVarObject_CAST(op) ((PyVarObject*)(op))
+
+#define Py_REFCNT(ob)           (_PyObject_CAST(ob)->ob_refcnt)
+#define Py_TYPE(ob)             (_PyObject_CAST(ob)->ob_type)
+#define Py_SIZE(ob)             (_PyVarObject_CAST(ob)->ob_size)
+
+/*
+Type objects contain a string containing the type name (to help somewhat
+in debugging), the allocation parameters (see PyObject_New() and
+PyObject_NewVar()),
+and methods for accessing objects of the type.  Methods are optional, a
+nil pointer meaning that particular kind of access is not available for
+this type.  The Py_DECREF() macro uses the tp_dealloc method without
+checking for a nil pointer; it should always be implemented except if
+the implementation can guarantee that the reference count will never
+reach zero (e.g., for statically allocated type objects).
+
+NB: the methods for certain type groups are now contained in separate
+method blocks.
+*/
+
+typedef PyObject * (*unaryfunc)(PyObject *);
+typedef PyObject * (*binaryfunc)(PyObject *, PyObject *);
+typedef PyObject * (*ternaryfunc)(PyObject *, PyObject *, PyObject *);
+typedef int (*inquiry)(PyObject *);
+typedef Py_ssize_t (*lenfunc)(PyObject *);
+typedef PyObject *(*ssizeargfunc)(PyObject *, Py_ssize_t);
+typedef PyObject *(*ssizessizeargfunc)(PyObject *, Py_ssize_t, Py_ssize_t);
+typedef int(*ssizeobjargproc)(PyObject *, Py_ssize_t, PyObject *);
+typedef int(*ssizessizeobjargproc)(PyObject *, Py_ssize_t, Py_ssize_t, PyObject *);
+typedef int(*objobjargproc)(PyObject *, PyObject *, PyObject *);
+
+typedef int (*objobjproc)(PyObject *, PyObject *);
+typedef int (*visitproc)(PyObject *, void *);
+typedef int (*traverseproc)(PyObject *, visitproc, void *);
+
+
+typedef void (*freefunc)(void *);
+typedef void (*destructor)(PyObject *);
+typedef PyObject *(*getattrfunc)(PyObject *, char *);
+typedef PyObject *(*getattrofunc)(PyObject *, PyObject *);
+typedef int (*setattrfunc)(PyObject *, char *, PyObject *);
+typedef int (*setattrofunc)(PyObject *, PyObject *, PyObject *);
+typedef PyObject *(*reprfunc)(PyObject *);
+typedef Py_hash_t (*hashfunc)(PyObject *);
+typedef PyObject *(*richcmpfunc) (PyObject *, PyObject *, int);
+typedef PyObject *(*getiterfunc) (PyObject *);
+typedef PyObject *(*iternextfunc) (PyObject *);
+typedef PyObject *(*descrgetfunc) (PyObject *, PyObject *, PyObject *);
+typedef int (*descrsetfunc) (PyObject *, PyObject *, PyObject *);
+typedef int (*initproc)(PyObject *, PyObject *, PyObject *);
+typedef PyObject *(*newfunc)(struct _typeobject *, PyObject *, PyObject *);
+typedef PyObject *(*allocfunc)(struct _typeobject *, Py_ssize_t);
+
+#ifdef Py_LIMITED_API
+/* In Py_LIMITED_API, PyTypeObject is an opaque structure. */
+typedef struct _typeobject PyTypeObject;
+#else
+/* PyTypeObject is defined in cpython/object.h */
+#endif
+
+typedef struct{
+    int slot;    /* slot id, see below */
+    void *pfunc; /* function pointer */
+} PyType_Slot;
+
+typedef struct{
+    const char* name;
+    int basicsize;
+    int itemsize;
+    unsigned int flags;
+    PyType_Slot *slots; /* terminated by slot==0. */
+} PyType_Spec;
+
+PyAPI_FUNC(PyObject*) PyType_FromSpec(PyType_Spec*);
+#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03030000
+PyAPI_FUNC(PyObject*) PyType_FromSpecWithBases(PyType_Spec*, PyObject*);
+#endif
+#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03040000
+PyAPI_FUNC(void*) PyType_GetSlot(struct _typeobject*, int);
+#endif
+
+/* Generic type check */
+PyAPI_FUNC(int) PyType_IsSubtype(struct _typeobject *, struct _typeobject *);
+#define PyObject_TypeCheck(ob, tp) \
+    (Py_TYPE(ob) == (tp) || PyType_IsSubtype(Py_TYPE(ob), (tp)))
+
+PyAPI_DATA(struct _typeobject) PyType_Type; /* built-in 'type' */
+PyAPI_DATA(struct _typeobject) PyBaseObject_Type; /* built-in 'object' */
+PyAPI_DATA(struct _typeobject) PySuper_Type; /* built-in 'super' */
+
+PyAPI_FUNC(unsigned long) PyType_GetFlags(struct _typeobject*);
+
+#define PyType_Check(op) \
+    PyType_FastSubclass(Py_TYPE(op), Py_TPFLAGS_TYPE_SUBCLASS)
+#define PyType_CheckExact(op) (Py_TYPE(op) == &PyType_Type)
+
+PyAPI_FUNC(int) PyType_Ready(struct _typeobject *);
+PyAPI_FUNC(PyObject *) PyType_GenericAlloc(struct _typeobject *, Py_ssize_t);
+PyAPI_FUNC(PyObject *) PyType_GenericNew(struct _typeobject *,
+                                               PyObject *, PyObject *);
+PyAPI_FUNC(unsigned int) PyType_ClearCache(void);
+PyAPI_FUNC(void) PyType_Modified(struct _typeobject *);
+
+/* Generic operations on objects */
+PyAPI_FUNC(PyObject *) PyObject_Repr(PyObject *);
+PyAPI_FUNC(PyObject *) PyObject_Str(PyObject *);
+PyAPI_FUNC(PyObject *) PyObject_ASCII(PyObject *);
+PyAPI_FUNC(PyObject *) PyObject_Bytes(PyObject *);
+PyAPI_FUNC(PyObject *) PyObject_RichCompare(PyObject *, PyObject *, int);
+PyAPI_FUNC(int) PyObject_RichCompareBool(PyObject *, PyObject *, int);
+PyAPI_FUNC(PyObject *) PyObject_GetAttrString(PyObject *, const char *);
+PyAPI_FUNC(int) PyObject_SetAttrString(PyObject *, const char *, PyObject *);
+PyAPI_FUNC(int) PyObject_HasAttrString(PyObject *, const char *);
+PyAPI_FUNC(PyObject *) PyObject_GetAttr(PyObject *, PyObject *);
+PyAPI_FUNC(int) PyObject_SetAttr(PyObject *, PyObject *, PyObject *);
+PyAPI_FUNC(int) PyObject_HasAttr(PyObject *, PyObject *);
+PyAPI_FUNC(PyObject *) PyObject_SelfIter(PyObject *);
+PyAPI_FUNC(PyObject *) PyObject_GenericGetAttr(PyObject *, PyObject *);
+PyAPI_FUNC(int) PyObject_GenericSetAttr(PyObject *,
+                                              PyObject *, PyObject *);
+#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03030000
+PyAPI_FUNC(int) PyObject_GenericSetDict(PyObject *, PyObject *, void *);
+#endif
+PyAPI_FUNC(Py_hash_t) PyObject_Hash(PyObject *);
+PyAPI_FUNC(Py_hash_t) PyObject_HashNotImplemented(PyObject *);
+PyAPI_FUNC(int) PyObject_IsTrue(PyObject *);
+PyAPI_FUNC(int) PyObject_Not(PyObject *);
+PyAPI_FUNC(int) PyCallable_Check(PyObject *);
+PyAPI_FUNC(void) PyObject_ClearWeakRefs(PyObject *);
+
+/* PyObject_Dir(obj) acts like Python builtins.dir(obj), returning a
+   list of strings.  PyObject_Dir(NULL) is like builtins.dir(),
+   returning the names of the current locals.  In this case, if there are
+   no current locals, NULL is returned, and PyErr_Occurred() is false.
+*/
+PyAPI_FUNC(PyObject *) PyObject_Dir(PyObject *);
+
+
+/* Helpers for printing recursive container types */
+PyAPI_FUNC(int) Py_ReprEnter(PyObject *);
+PyAPI_FUNC(void) Py_ReprLeave(PyObject *);
+
+/* Flag bits for printing: */
+#define Py_PRINT_RAW    1       /* No string quotes etc. */
+
+/*
+Type flags (tp_flags)
+
+These flags are used to change expected features and behavior for a
+particular type.
+
+Arbitration of the flag bit positions will need to be coordinated among
+all extension writers who publicly release their extensions (this will
+be fewer than you might expect!).
+
+Most flags were removed as of Python 3.0 to make room for new flags.  (Some
+flags are not for backwards compatibility but to indicate the presence of an
+optional feature; these flags remain of course.)
+
+Type definitions should use Py_TPFLAGS_DEFAULT for their tp_flags value.
+
+Code can use PyType_HasFeature(type_ob, flag_value) to test whether the
+given type object has a specified feature.
+*/
+
+/* Set if the type object is dynamically allocated */
+#define Py_TPFLAGS_HEAPTYPE (1UL << 9)
+
+/* Set if the type allows subclassing */
+#define Py_TPFLAGS_BASETYPE (1UL << 10)
+
+/* Set if the type implements the vectorcall protocol (PEP 590) */
+#ifndef Py_LIMITED_API
+#define _Py_TPFLAGS_HAVE_VECTORCALL (1UL << 11)
+#endif
+
+/* Set if the type is 'ready' -- fully initialized */
+#define Py_TPFLAGS_READY (1UL << 12)
+
+/* Set while the type is being 'readied', to prevent recursive ready calls */
+#define Py_TPFLAGS_READYING (1UL << 13)
+
+/* Objects support garbage collection (see objimpl.h) */
+#define Py_TPFLAGS_HAVE_GC (1UL << 14)
+
+/* These two bits are preserved for Stackless Python, next after this is 17 */
+#ifdef STACKLESS
+#define Py_TPFLAGS_HAVE_STACKLESS_EXTENSION (3UL << 15)
+#else
+#define Py_TPFLAGS_HAVE_STACKLESS_EXTENSION 0
+#endif
+
+/* Objects behave like an unbound method */
+#define Py_TPFLAGS_METHOD_DESCRIPTOR (1UL << 17)
+
+/* Objects support type attribute cache */
+#define Py_TPFLAGS_HAVE_VERSION_TAG   (1UL << 18)
+#define Py_TPFLAGS_VALID_VERSION_TAG  (1UL << 19)
+
+/* Type is abstract and cannot be instantiated */
+#define Py_TPFLAGS_IS_ABSTRACT (1UL << 20)
+
+/* These flags are used to determine if a type is a subclass. */
+#define Py_TPFLAGS_LONG_SUBCLASS        (1UL << 24)
+#define Py_TPFLAGS_LIST_SUBCLASS        (1UL << 25)
+#define Py_TPFLAGS_TUPLE_SUBCLASS       (1UL << 26)
+#define Py_TPFLAGS_BYTES_SUBCLASS       (1UL << 27)
+#define Py_TPFLAGS_UNICODE_SUBCLASS     (1UL << 28)
+#define Py_TPFLAGS_DICT_SUBCLASS        (1UL << 29)
+#define Py_TPFLAGS_BASE_EXC_SUBCLASS    (1UL << 30)
+#define Py_TPFLAGS_TYPE_SUBCLASS        (1UL << 31)
+
+#define Py_TPFLAGS_DEFAULT  ( \
+                 Py_TPFLAGS_HAVE_STACKLESS_EXTENSION | \
+                 Py_TPFLAGS_HAVE_VERSION_TAG | \
+                0)
+
+/* NOTE: The following flags reuse lower bits (removed as part of the
+ * Python 3.0 transition). */
+
+/* The following flag is kept for compatibility.  Starting with 3.8,
+ * binary compatibility of C extensions accross feature releases of
+ * Python is not supported anymore, except when using the stable ABI.
+ */
+
+/* Type structure has tp_finalize member (3.4) */
+#define Py_TPFLAGS_HAVE_FINALIZE (1UL << 0)
+
+#ifdef Py_LIMITED_API
+#  define PyType_HasFeature(t,f)  ((PyType_GetFlags(t) & (f)) != 0)
+#endif
+#define PyType_FastSubclass(t,f)  PyType_HasFeature(t,f)
+
+
+/*
+The macros Py_INCREF(op) and Py_DECREF(op) are used to increment or decrement
+reference counts.  Py_DECREF calls the object's deallocator function when
+the refcount falls to 0; for
+objects that don't contain references to other objects or heap memory
+this can be the standard function free().  Both macros can be used
+wherever a void expression is allowed.  The argument must not be a
+NULL pointer.  If it may be NULL, use Py_XINCREF/Py_XDECREF instead.
+The macro _Py_NewReference(op) initialize reference counts to 1, and
+in special builds (Py_REF_DEBUG, Py_TRACE_REFS) performs additional
+bookkeeping appropriate to the special build.
+
+We assume that the reference count field can never overflow; this can
+be proven when the size of the field is the same as the pointer size, so
+we ignore the possibility.  Provided a C int is at least 32 bits (which
+is implicitly assumed in many parts of this code), that's enough for
+about 2**31 references to an object.
+
+XXX The following became out of date in Python 2.2, but I'm not sure
+XXX what the full truth is now.  Certainly, heap-allocated type objects
+XXX can and should be deallocated.
+Type objects should never be deallocated; the type pointer in an object
+is not considered to be a reference to the type object, to save
+complications in the deallocation function.  (This is actually a
+decision that's up to the implementer of each new type so if you want,
+you can count such references to the type object.)
+*/
+
+/* First define a pile of simple helper macros, one set per special
+ * build symbol.  These either expand to the obvious things, or to
+ * nothing at all when the special mode isn't in effect.  The main
+ * macros can later be defined just once then, yet expand to different
+ * things depending on which special build options are and aren't in effect.
+ * Trust me <wink>:  while painful, this is 20x easier to understand than,
+ * e.g, defining _Py_NewReference five different times in a maze of nested
+ * #ifdefs (we used to do that -- it was impenetrable).
+ */
+#ifdef Py_REF_DEBUG
+PyAPI_DATA(Py_ssize_t) _Py_RefTotal;
+PyAPI_FUNC(void) _Py_NegativeRefcount(const char *filename, int lineno,
+                                      PyObject *op);
+PyAPI_FUNC(Py_ssize_t) _Py_GetRefTotal(void);
+#define _Py_INC_REFTOTAL        _Py_RefTotal++
+#define _Py_DEC_REFTOTAL        _Py_RefTotal--
+
+/* Py_REF_DEBUG also controls the display of refcounts and memory block
+ * allocations at the interactive prompt and at interpreter shutdown
+ */
+PyAPI_FUNC(void) _PyDebug_PrintTotalRefs(void);
+#else
+#define _Py_INC_REFTOTAL
+#define _Py_DEC_REFTOTAL
+#endif /* Py_REF_DEBUG */
+
+#ifdef COUNT_ALLOCS
+PyAPI_FUNC(void) _Py_inc_count(struct _typeobject *);
+PyAPI_FUNC(void) _Py_dec_count(struct _typeobject *);
+#define _Py_INC_TPALLOCS(OP)    _Py_inc_count(Py_TYPE(OP))
+#define _Py_INC_TPFREES(OP)     _Py_dec_count(Py_TYPE(OP))
+#define _Py_DEC_TPFREES(OP)     Py_TYPE(OP)->tp_frees--
+#define _Py_COUNT_ALLOCS_COMMA  ,
+#else
+#define _Py_INC_TPALLOCS(OP)
+#define _Py_INC_TPFREES(OP)
+#define _Py_DEC_TPFREES(OP)
+#define _Py_COUNT_ALLOCS_COMMA
+#endif /* COUNT_ALLOCS */
+
+/* Update the Python traceback of an object. This function must be called
+   when a memory block is reused from a free list. */
+PyAPI_FUNC(int) _PyTraceMalloc_NewReference(PyObject *op);
+
+#ifdef Py_TRACE_REFS
+/* Py_TRACE_REFS is such major surgery that we call external routines. */
+PyAPI_FUNC(void) _Py_NewReference(PyObject *);
+PyAPI_FUNC(void) _Py_ForgetReference(PyObject *);
+PyAPI_FUNC(void) _Py_PrintReferences(FILE *);
+PyAPI_FUNC(void) _Py_PrintReferenceAddresses(FILE *);
+PyAPI_FUNC(void) _Py_AddToAllObjects(PyObject *, int force);
+#else
+/* Without Py_TRACE_REFS, there's little enough to do that we expand code
+   inline. */
+static inline void _Py_NewReference(PyObject *op)
+{
+    if (_Py_tracemalloc_config.tracing) {
+        _PyTraceMalloc_NewReference(op);
+    }
+    _Py_INC_TPALLOCS(op);
+    _Py_INC_REFTOTAL;
+    Py_REFCNT(op) = 1;
+}
+
+static inline void _Py_ForgetReference(PyObject *op)
+{
+    (void)op; /* may be unused, shut up -Wunused-parameter */
+    _Py_INC_TPFREES(op);
+}
+#endif /* !Py_TRACE_REFS */
+
+
+PyAPI_FUNC(void) _Py_Dealloc(PyObject *);
+
+static inline void _Py_INCREF(PyObject *op)
+{
+    _Py_INC_REFTOTAL;
+    op->ob_refcnt++;
+}
+
+#define Py_INCREF(op) _Py_INCREF(_PyObject_CAST(op))
+
+static inline void _Py_DECREF(const char *filename, int lineno,
+                              PyObject *op)
+{
+    (void)filename; /* may be unused, shut up -Wunused-parameter */
+    (void)lineno; /* may be unused, shut up -Wunused-parameter */
+    _Py_DEC_REFTOTAL;
+    if (--op->ob_refcnt != 0) {
+#ifdef Py_REF_DEBUG
+        if (op->ob_refcnt < 0) {
+            _Py_NegativeRefcount(filename, lineno, op);
+        }
+#endif
+    }
+    else {
+        _Py_Dealloc(op);
+    }
+}
+
+#define Py_DECREF(op) _Py_DECREF(__FILE__, __LINE__, _PyObject_CAST(op))
+
+
+/* Safely decref `op` and set `op` to NULL, especially useful in tp_clear
+ * and tp_dealloc implementations.
+ *
+ * Note that "the obvious" code can be deadly:
+ *
+ *     Py_XDECREF(op);
+ *     op = NULL;
+ *
+ * Typically, `op` is something like self->containee, and `self` is done
+ * using its `containee` member.  In the code sequence above, suppose
+ * `containee` is non-NULL with a refcount of 1.  Its refcount falls to
+ * 0 on the first line, which can trigger an arbitrary amount of code,
+ * possibly including finalizers (like __del__ methods or weakref callbacks)
+ * coded in Python, which in turn can release the GIL and allow other threads
+ * to run, etc.  Such code may even invoke methods of `self` again, or cause
+ * cyclic gc to trigger, but-- oops! --self->containee still points to the
+ * object being torn down, and it may be in an insane state while being torn
+ * down.  This has in fact been a rich historic source of miserable (rare &
+ * hard-to-diagnose) segfaulting (and other) bugs.
+ *
+ * The safe way is:
+ *
+ *      Py_CLEAR(op);
+ *
+ * That arranges to set `op` to NULL _before_ decref'ing, so that any code
+ * triggered as a side-effect of `op` getting torn down no longer believes
+ * `op` points to a valid object.
+ *
+ * There are cases where it's safe to use the naive code, but they're brittle.
+ * For example, if `op` points to a Python integer, you know that destroying
+ * one of those can't cause problems -- but in part that relies on that
+ * Python integers aren't currently weakly referencable.  Best practice is
+ * to use Py_CLEAR() even if you can't think of a reason for why you need to.
+ */
+#define Py_CLEAR(op)                            \
+    do {                                        \
+        PyObject *_py_tmp = _PyObject_CAST(op); \
+        if (_py_tmp != NULL) {                  \
+            (op) = NULL;                        \
+            Py_DECREF(_py_tmp);                 \
+        }                                       \
+    } while (0)
+
+/* Function to use in case the object pointer can be NULL: */
+static inline void _Py_XINCREF(PyObject *op)
+{
+    if (op != NULL) {
+        Py_INCREF(op);
+    }
+}
+
+#define Py_XINCREF(op) _Py_XINCREF(_PyObject_CAST(op))
+
+static inline void _Py_XDECREF(PyObject *op)
+{
+    if (op != NULL) {
+        Py_DECREF(op);
+    }
+}
+
+#define Py_XDECREF(op) _Py_XDECREF(_PyObject_CAST(op))
+
+/*
+These are provided as conveniences to Python runtime embedders, so that
+they can have object code that is not dependent on Python compilation flags.
+*/
+PyAPI_FUNC(void) Py_IncRef(PyObject *);
+PyAPI_FUNC(void) Py_DecRef(PyObject *);
+
+/*
+_Py_NoneStruct is an object of undefined type which can be used in contexts
+where NULL (nil) is not suitable (since NULL often means 'error').
+
+Don't forget to apply Py_INCREF() when returning this value!!!
+*/
+PyAPI_DATA(PyObject) _Py_NoneStruct; /* Don't use this directly */
+#define Py_None (&_Py_NoneStruct)
+
+/* Macro for returning Py_None from a function */
+#define Py_RETURN_NONE return Py_INCREF(Py_None), Py_None
+
+/*
+Py_NotImplemented is a singleton used to signal that an operation is
+not implemented for a given type combination.
+*/
+PyAPI_DATA(PyObject) _Py_NotImplementedStruct; /* Don't use this directly */
+#define Py_NotImplemented (&_Py_NotImplementedStruct)
+
+/* Macro for returning Py_NotImplemented from a function */
+#define Py_RETURN_NOTIMPLEMENTED \
+    return Py_INCREF(Py_NotImplemented), Py_NotImplemented
+
+/* Rich comparison opcodes */
+#define Py_LT 0
+#define Py_LE 1
+#define Py_EQ 2
+#define Py_NE 3
+#define Py_GT 4
+#define Py_GE 5
+
+/*
+ * Macro for implementing rich comparisons
+ *
+ * Needs to be a macro because any C-comparable type can be used.
+ */
+#define Py_RETURN_RICHCOMPARE(val1, val2, op)                               \
+    do {                                                                    \
+        switch (op) {                                                       \
+        case Py_EQ: if ((val1) == (val2)) Py_RETURN_TRUE; Py_RETURN_FALSE;  \
+        case Py_NE: if ((val1) != (val2)) Py_RETURN_TRUE; Py_RETURN_FALSE;  \
+        case Py_LT: if ((val1) < (val2)) Py_RETURN_TRUE; Py_RETURN_FALSE;   \
+        case Py_GT: if ((val1) > (val2)) Py_RETURN_TRUE; Py_RETURN_FALSE;   \
+        case Py_LE: if ((val1) <= (val2)) Py_RETURN_TRUE; Py_RETURN_FALSE;  \
+        case Py_GE: if ((val1) >= (val2)) Py_RETURN_TRUE; Py_RETURN_FALSE;  \
+        default:                                                            \
+            Py_UNREACHABLE();                                               \
+        }                                                                   \
+    } while (0)
+
+
+/*
+More conventions
+================
+
+Argument Checking
+-----------------
+
+Functions that take objects as arguments normally don't check for nil
+arguments, but they do check the type of the argument, and return an
+error if the function doesn't apply to the type.
+
+Failure Modes
+-------------
+
+Functions may fail for a variety of reasons, including running out of
+memory.  This is communicated to the caller in two ways: an error string
+is set (see errors.h), and the function result differs: functions that
+normally return a pointer return NULL for failure, functions returning
+an integer return -1 (which could be a legal return value too!), and
+other functions return 0 for success and -1 for failure.
+Callers should always check for errors before using the result.  If
+an error was set, the caller must either explicitly clear it, or pass
+the error on to its caller.
+
+Reference Counts
+----------------
+
+It takes a while to get used to the proper usage of reference counts.
+
+Functions that create an object set the reference count to 1; such new
+objects must be stored somewhere or destroyed again with Py_DECREF().
+Some functions that 'store' objects, such as PyTuple_SetItem() and
+PyList_SetItem(),
+don't increment the reference count of the object, since the most
+frequent use is to store a fresh object.  Functions that 'retrieve'
+objects, such as PyTuple_GetItem() and PyDict_GetItemString(), also
+don't increment
+the reference count, since most frequently the object is only looked at
+quickly.  Thus, to retrieve an object and store it again, the caller
+must call Py_INCREF() explicitly.
+
+NOTE: functions that 'consume' a reference count, like
+PyList_SetItem(), consume the reference even if the object wasn't
+successfully stored, to simplify error handling.
+
+It seems attractive to make other functions that take an object as
+argument consume a reference count; however, this may quickly get
+confusing (even the current practice is already confusing).  Consider
+it carefully, it may save lots of calls to Py_INCREF() and Py_DECREF() at
+times.
+*/
+
+
+/* Trashcan mechanism, thanks to Christian Tismer.
+
+When deallocating a container object, it's possible to trigger an unbounded
+chain of deallocations, as each Py_DECREF in turn drops the refcount on "the
+next" object in the chain to 0.  This can easily lead to stack overflows,
+especially in threads (which typically have less stack space to work with).
+
+A container object can avoid this by bracketing the body of its tp_dealloc
+function with a pair of macros:
+
+static void
+mytype_dealloc(mytype *p)
+{
+    ... declarations go here ...
+
+    PyObject_GC_UnTrack(p);        // must untrack first
+    Py_TRASHCAN_BEGIN(p, mytype_dealloc)
+    ... The body of the deallocator goes here, including all calls ...
+    ... to Py_DECREF on contained objects.                         ...
+    Py_TRASHCAN_END                // there should be no code after this
+}
+
+CAUTION:  Never return from the middle of the body!  If the body needs to
+"get out early", put a label immediately before the Py_TRASHCAN_END
+call, and goto it.  Else the call-depth counter (see below) will stay
+above 0 forever, and the trashcan will never get emptied.
+
+How it works:  The BEGIN macro increments a call-depth counter.  So long
+as this counter is small, the body of the deallocator is run directly without
+further ado.  But if the counter gets large, it instead adds p to a list of
+objects to be deallocated later, skips the body of the deallocator, and
+resumes execution after the END macro.  The tp_dealloc routine then returns
+without deallocating anything (and so unbounded call-stack depth is avoided).
+
+When the call stack finishes unwinding again, code generated by the END macro
+notices this, and calls another routine to deallocate all the objects that
+may have been added to the list of deferred deallocations.  In effect, a
+chain of N deallocations is broken into (N-1)/(PyTrash_UNWIND_LEVEL-1) pieces,
+with the call stack never exceeding a depth of PyTrash_UNWIND_LEVEL.
+
+Since the tp_dealloc of a subclass typically calls the tp_dealloc of the base
+class, we need to ensure that the trashcan is only triggered on the tp_dealloc
+of the actual class being deallocated. Otherwise we might end up with a
+partially-deallocated object. To check this, the tp_dealloc function must be
+passed as second argument to Py_TRASHCAN_BEGIN().
+*/
+
+/* The new thread-safe private API, invoked by the macros below. */
+PyAPI_FUNC(void) _PyTrash_thread_deposit_object(PyObject*);
+PyAPI_FUNC(void) _PyTrash_thread_destroy_chain(void);
+
+#define PyTrash_UNWIND_LEVEL 50
+
+#define Py_TRASHCAN_BEGIN_CONDITION(op, cond) \
+    do { \
+        PyThreadState *_tstate = NULL; \
+        /* If "cond" is false, then _tstate remains NULL and the deallocator \
+         * is run normally without involving the trashcan */ \
+        if (cond) { \
+            _tstate = PyThreadState_GET(); \
+            if (_tstate->trash_delete_nesting >= PyTrash_UNWIND_LEVEL) { \
+                /* Store the object (to be deallocated later) and jump past \
+                 * Py_TRASHCAN_END, skipping the body of the deallocator */ \
+                _PyTrash_thread_deposit_object(_PyObject_CAST(op)); \
+                break; \
+            } \
+            ++_tstate->trash_delete_nesting; \
+        }
+        /* The body of the deallocator is here. */
+#define Py_TRASHCAN_END \
+        if (_tstate) { \
+            --_tstate->trash_delete_nesting; \
+            if (_tstate->trash_delete_later && _tstate->trash_delete_nesting <= 0) \
+                _PyTrash_thread_destroy_chain(); \
+        } \
+    } while (0);
+
+#define Py_TRASHCAN_BEGIN(op, dealloc) Py_TRASHCAN_BEGIN_CONDITION(op, \
+        Py_TYPE(op)->tp_dealloc == (destructor)(dealloc))
+
+/* For backwards compatibility, these macros enable the trashcan
+ * unconditionally */
+#define Py_TRASHCAN_SAFE_BEGIN(op) Py_TRASHCAN_BEGIN_CONDITION(op, 1)
+#define Py_TRASHCAN_SAFE_END(op) Py_TRASHCAN_END
+
+
+#ifndef Py_LIMITED_API
+#  define Py_CPYTHON_OBJECT_H
+#  include  "cpython/object.h"
+#  undef Py_CPYTHON_OBJECT_H
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* !Py_OBJECT_H */