gh-72971: Clarify the special no-TypeError behavior for equality (#110729)

diff --git a/Doc/reference/datamodel.rst b/Doc/reference/datamodel.rst
index 82106a41c4c4ed796b790115d3a816b8d8d3e88d..75b656f385d34bbf26812e1b0baeaaf9bd992772 100644 (file)
--- a/Doc/reference/datamodel.rst
+++ b/Doc/reference/datamodel.rst
@@ -1812,12 +1812,15 @@ Basic customization
    rather, :meth:`__lt__` and :meth:`__gt__` are each other's reflection,
    :meth:`__le__` and :meth:`__ge__` are each other's reflection, and
    :meth:`__eq__` and :meth:`__ne__` are their own reflection.
-   If the operands are of different types, and right operand's type is
+   If the operands are of different types, and the right operand's type is
    a direct or indirect subclass of the left operand's type,
    the reflected method of the right operand has priority, otherwise
    the left operand's method has priority.  Virtual subclassing is
    not considered.
 
+   When no appropriate method returns any value other than :data:`NotImplemented`, the
+   ``==`` and ``!=`` operators will fall back to ``is`` and ``is not``, respectively.
+
 .. method:: object.__hash__(self)
 
    .. index::