ein ihaskell, native auto-completion is not working:

here is my the piece of my .emacs code that i am trying to use:

;;------------------------------------------------------------------
;; emacs-ipython-notebook configuration:
(add-hook 'after-init-hook 'global-company-mode)

(require 'haskell-doc)
(require 'company)
(require 'ein)
(require 'ein-jupyter)
;; (setq ein:log-set-level 'debug)
(setq ein:polymode t)
(setq ein:notebook-modes '(ein:notebook-multilang-mode))
(setq ein:completion-backend 'ein:use-none-backend)

(add-hook 'haskell-mode-hook
          (lambda ()
            (set (make-local-variable 'company-backends)
                 (append '((company-capf company-dabbrev-code))
                         company-backends))))
;;------------------------------------------------------------------