Mean while the following solves it:
(add-hook 'python-mode-hook (lambda () (define-key python-mode-map (kbd "<C-backspace>") 'subword-backward-kill) ))
Mean while the following solves it:
(add-hook 'python-mode-hook (lambda ()
(define- key python-mode-map (kbd "<C-backspace>") 'subword- backward- kill)
))