切片物件
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PyTypeObject PySlice_Type

   The type object for slice objects.  This is the same as "slice" in
   the Python layer.

int PySlice_Check(PyObject *ob)

   Return true if *ob* is a slice object; *ob* must not be *NULL*.

PyObject* PySlice_New(PyObject *start, PyObject *stop, PyObject *step)
    *Return value: New reference.*

   Return a new slice object with the given values.  The *start*,
   *stop*, and *step* parameters are used as the values of the slice
   object attributes of the same names.  Any of the values may be
   *NULL*, in which case the "None" will be used for the corresponding
   attribute.  Return *NULL* if the new object could not be allocated.

int PySlice_GetIndices(PyObject *slice, Py_ssize_t length, Py_ssize_t *start, Py_ssize_t *stop, Py_ssize_t *step)

   Retrieve the start, stop and step indices from the slice object
   *slice*, assuming a sequence of length *length*. Treats indices
   greater than *length* as errors.

   Returns "0" on success and "-1" on error with no exception set
   (unless one of the indices was not "None" and failed to be
   converted to an integer, in which case "-1" is returned with an
   exception set).

   You probably do not want to use this function.

   3.2 版更變: The parameter type for the *slice* parameter was
   "PySliceObject*" before.

int PySlice_GetIndicesEx(PyObject *slice, Py_ssize_t length, Py_ssize_t *start, Py_ssize_t *stop, Py_ssize_t *step, Py_ssize_t *slicelength)

   Usable replacement for "PySlice_GetIndices()".  Retrieve the start,
   stop, and step indices from the slice object *slice* assuming a
   sequence of length *length*, and store the length of the slice in
   *slicelength*.  Out of bounds indices are clipped in a manner
   consistent with the handling of normal slices.

   Returns "0" on success and "-1" on error with exception set.

   3.2 版更變: The parameter type for the *slice* parameter was
   "PySliceObject*" before.


Ellipsis Object
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PyObject *Py_Ellipsis

   The Python "Ellipsis" object.  This object has no methods.  It
   needs to be treated just like any other object with respect to
   reference counts.  Like "Py_None" it is a singleton object.
