diff --git a/lisp/emacs-lisp/cl-macs.el b/lisp/emacs-lisp/cl-macs.el
index 04567917189..8fdafe18c50 100644
--- a/lisp/emacs-lisp/cl-macs.el
+++ b/lisp/emacs-lisp/cl-macs.el
@@ -3683,8 +3683,7 @@ macro that returns its `&whole' argument."
          cl-tree-equal
 
          ;; Functions that mutate and return a list.
-         ;;cl-delete
-         cl-delete-if cl-delete-if-not
+         cl-delete cl-delete-if cl-delete-if-not
          cl-delete-duplicates
          cl-nsubst cl-nsubst-if cl-nsubst-if-not
          cl-nsubstitute cl-nsubstitute-if cl-nsubstitute-if-not
diff --git a/lisp/progmodes/python.el b/lisp/progmodes/python.el
index 5bb15c60956..f9b645cc3df 100644
--- a/lisp/progmodes/python.el
+++ b/lisp/progmodes/python.el
@@ -2720,8 +2720,7 @@ dedicated to the current buffer or its project (if one is found)."
 (defmacro python-shell--add-to-path-with-priority (pathvar paths)
   "Modify PATHVAR and ensure PATHS are added only once at beginning."
   `(dolist (path (reverse ,paths))
-     (cl-delete path ,pathvar :test #'string=)
-     (cl-pushnew path ,pathvar :test #'string=)))
+     (setq ,pathvar (cons path (cl-delete path ,pathvar :test #'string=)))))
 
 (defun python-shell-calculate-pythonpath ()
   "Calculate the PYTHONPATH using `python-shell-extra-pythonpaths'."