hideshow config for python

hideshow-config.el

(require 'hideshow)
(define-key hs-minor-mode-map (kbd "C-^") 'hs-toggle-hiding)
(add-hook 'python-mode-hook 'hs-minor-mode)
(defun display-code-line-counts (ov)
  (when (eq 'code (overlay-get ov 'hs))
    (overlay-put ov 'display
                 (format "   ... [%d]"
                         (count-lines (overlay-start ov)
                                      (overlay-end ov))))
    (overlay-put ov 'face '(:foreground "yellow green"))))
(setq hs-set-up-overlay 'display-code-line-counts)

hs-config-for-python.el

(defvar my/py-hide-show-keywords '("class" "def" "elif" "else" "except"
                                   "for" "if" "while" "finally" "try" "with"))
(defun my/replace-hs-special ()
  (setq hs-special-modes-alist
        (remove-if #'(lambda (x) (equal 'python-mode (car x)))
                   hs-special-modes-alist))
  (push (list
         'python-mode
         (mapconcat #'(lambda (x) (concat "^\\s-*" x "\\>"))
                    my/py-hide-show-keywords "\\|")
         "^\\s-*"
         "#"
         #'(lambda (x) (python-nav-end-of-block))
         nil)
        hs-special-modes-alist)
  (hs-grok-mode-type))
(add-hook 'python-mode-hook 'my/replace-hs-special)

python-mode-hook invokes #'hs-minor-mode after #'my/replace-hs-special

How do you know this, is there any tool to debug this?

It may not be accurate. I just confirmed that when I swapped the order of (add-hook 'python-mode-hook 'my/replace-hs-special) and (add-hook 'python-mode-hook 'hs-minor-mode), it didn't work.

I didn't use any debugging tools.

That's where the problem lies. I actually didn't config (add-hook 'python-mode-hook 'hs-minor-mode) at all.