tags-completion-at-point-function over python-completion-at-point as latter doesn't work for me in Cygwin.
--- a/.emacs-my Sun Jan 31 12:20:16 2021 +0200
+++ b/.emacs-my Sun Jan 31 12:23:23 2021 +0200
@@ -3188,6 +3188,7 @@
;; (add-hook 'python-mode-hook 'turn-on-eldoc-mode)
(defun my-python-mode-hook ()
+ (setq completion-at-point-functions '(tags-completion-at-point-function python-completion-at-point))
(when (and (eq window-system 'w32) (fboundp 'prettify-symbols-mode))
(prettify-symbols-mode -1)))
(add-hook 'python-mode-hook 'my-python-mode-hook)