Move __missing__ after __delitem__ in Data model. (GH-10923)

Doc/reference/datamodel.rst

@@ -2146,6 +2146,8 @@ through the container; for mappings, :meth:`__iter__` should be the same as
    .. versionadded:: 3.4
 
 
+.. index:: object: slice
+
 .. note::
 
    Slicing is done exclusively with the following three methods.  A call like ::
@@ -2161,8 +2163,6 @@ through the container; for mappings, :meth:`__iter__` should be the same as
 
 .. method:: object.__getitem__(self, key)
 
-   .. index:: object: slice
-
    Called to implement evaluation of ``self[key]``. For sequence types, the
    accepted keys should be integers and slice objects.  Note that the special
    interpretation of negative indexes (if the class wishes to emulate a sequence
@@ -2178,12 +2178,6 @@ through the container; for mappings, :meth:`__iter__` should be the same as
       indexes to allow proper detection of the end of the sequence.
 
 
-.. method:: object.__missing__(self, key)
-
-   Called by :class:`dict`\ .\ :meth:`__getitem__` to implement ``self[key]`` for dict subclasses
-   when key is not in the dictionary.
-
-
 .. method:: object.__setitem__(self, key, value)
 
    Called to implement assignment to ``self[key]``.  Same note as for
@@ -2202,6 +2196,12 @@ through the container; for mappings, :meth:`__iter__` should be the same as
    values as for the :meth:`__getitem__` method.
 
 
+.. method:: object.__missing__(self, key)
+
+   Called by :class:`dict`\ .\ :meth:`__getitem__` to implement ``self[key]`` for dict subclasses
+   when key is not in the dictionary.
+
+
 .. method:: object.__iter__(self)
 
    This method is called when an iterator is required for a container. This method