Ensure wordnut installation in its own section

README.org

@@ -238,7 +238,6 @@ The [[info:emacs#Init File][init file (info)]] does not load the ~custom-file~ a
        smartparens        ; smart editing of character pairs
        vertico            ; VERTical Interactive Completion
        wgrep              ; open a writable grep buffer
-       wordnut            ; WordNet lexical database
        writegood-mode     ; bullshit and weasel-word detector
        xr                 ; undo rx to grok regular expressions
        yasnippet)))       ; code or text template expansion
@@ -2414,6 +2413,30 @@ non-interactive =org-element= functions to an =Emacs-lisp= buffer.
          (org-heading-components) grok-org-output))))
 #+end_src
 
+** Grammar, spelling, and style tools
+:PROPERTIES:
+:CUSTOM_ID: sec:writing
+:END:
+
+*** [[https://wordnet.princeton.edu/][Wordnet]]
+:PROPERTIES:
+:CUSTOM_ID: sec:writing
+:END:
+
+The [[https://github.com/gromnitsky/wordnut#readme][wordnut]] package is a major mode interface to [[https://wordnet.princeton.edu/][Wordnet]], a lexical database for
+the English language.  Listing [[lst:check-wordnut]] checks whether the system meets
+the [[https://github.com/gromnitsky/wordnut#readme][wordnut]] prerequisites.
+
+#+caption[System check for =wordnut=]:
+#+caption: System check for =wordnut=.
+#+name: lst:check-wordnut
+#+begin_src emacs-lisp
+  (when (ensure-package-installation
+         'wordnut) ; WordNet lexical database interface
+    (unless (executable-find "wn")
+      (message "`wordnut' fails to find the `wn' executable")))
+#+end_src
+
 * Programming
 :PROPERTIES:
 :CUSTOM_ID: sec:programming
@@ -2913,9 +2936,10 @@ index bf312f6..4758b53 100644
 #+end_src
 :end:
 
-*** [[https://github.com/pythonic-emacs/blacken#readme][Blacken]]
+*** [[https://github.com/pythonic-emacs/blacken#readme][Blacken]]                                                        :noexport:
 :PROPERTIES:
 :CUSTOM_ID: sec:blacken
+:header-args:emacs-lisp: :tangle no
 :END:
 Listing [[lst:configure-blacken]] configures [[https://github.com/pythonic-emacs/blacken#readme][blacken]] to format Python code with the
 [[https://black.readthedocs.io/en/stable/index.html][Python Black code formatter]].