Type Objects
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PyTypeObject

   The C structure of the objects used to describe built-in types.

PyObject* PyType_Type

   This is the type object for type objects; it is the same object as
   "type" in the Python layer.

int PyType_Check(PyObject *o)

   Return true if the object *o* is a type object, including instances
   of types derived from the standard type object.  Return false in
   all other cases.

int PyType_CheckExact(PyObject *o)

   Return true if the object *o* is a type object, but not a subtype
   of the standard type object.  Return false in all other cases.

unsigned int PyType_ClearCache()

   Clear the internal lookup cache. Return the current version tag.

unsigned long PyType_GetFlags(PyTypeObject* type)

   Return the "tp_flags" member of *type*. This function is primarily
   meant for use with *Py_LIMITED_API*; the individual flag bits are
   guaranteed to be stable across Python releases, but access to
   "tp_flags" itself is not part of the limited API.

   New in version 3.2.

   Changed in version 3.4: The return type is now "unsigned long"
   rather than "long".

void PyType_Modified(PyTypeObject *type)

   Invalidate the internal lookup cache for the type and all of its
   subtypes.  This function must be called after any manual
   modification of the attributes or base classes of the type.

int PyType_HasFeature(PyTypeObject *o, int feature)

   Return true if the type object *o* sets the feature *feature*.
   Type features are denoted by single bit flags.

int PyType_IS_GC(PyTypeObject *o)

   Return true if the type object includes support for the cycle
   detector; this tests the type flag "Py_TPFLAGS_HAVE_GC".

int PyType_IsSubtype(PyTypeObject *a, PyTypeObject *b)

   Return true if *a* is a subtype of *b*.

   This function only checks for actual subtypes, which means that
   "__subclasscheck__()" is not called on *b*.  Call
   "PyObject_IsSubclass()" to do the same check that "issubclass()"
   would do.

PyObject* PyType_GenericAlloc(PyTypeObject *type, Py_ssize_t nitems)
    *Return value: New reference.*

   Generic handler for the "tp_alloc" slot of a type object.  Use
   Python’s default memory allocation mechanism to allocate a new
   instance and initialize all its contents to *NULL*.

PyObject* PyType_GenericNew(PyTypeObject *type, PyObject *args, PyObject *kwds)
    *Return value: New reference.*

   Generic handler for the "tp_new" slot of a type object.  Create a
   new instance using the type’s "tp_alloc" slot.

int PyType_Ready(PyTypeObject *type)

   Finalize a type object.  This should be called on all type objects
   to finish their initialization.  This function is responsible for
   adding inherited slots from a type’s base class.  Return "0" on
   success, or return "-1" and sets an exception on error.

PyObject* PyType_FromSpec(PyType_Spec *spec)
    *Return value: New reference.*

   Creates and returns a heap type object from the *spec* passed to
   the function.

PyObject* PyType_FromSpecWithBases(PyType_Spec *spec, PyObject *bases)
    *Return value: New reference.*

   Creates and returns a heap type object from the *spec*. In addition
   to that, the created heap type contains all types contained by the
   *bases* tuple as base types. This allows the caller to reference
   other heap types as base types.

   New in version 3.3.

void* PyType_GetSlot(PyTypeObject *type, int slot)

   Return the function pointer stored in the given slot. If the result
   is *NULL*, this indicates that either the slot is *NULL*, or that
   the function was called with invalid parameters. Callers will
   typically cast the result pointer into the appropriate function
   type.

   New in version 3.4.
