Add support for Python mode in info-lookup-symbol

* lisp/info-look.el (:mode): Add support for Python mode
(bug#31405).

lisp/info-look.el

@@ -900,6 +900,10 @@ Return nil if there is nothing appropriate in the buffer near point."
 	      "^" "\\b"))
  :parse-rule "[$@%]?\\([_a-zA-Z0-9]+\\|[^a-zA-Z]\\)")
 
+(info-lookup-maybe-add-help
+ :mode 'python-mode
+ :doc-spec '(("(python)Index")))
+
 (info-lookup-maybe-add-help
  :mode 'cperl-mode
  :regexp "[$@%][^a-zA-Z]\\|\\$\\^[A-Z]\\|[$@%]?[a-zA-Z][_a-zA-Z0-9]*"