emacs里面定义的快捷键出问题

(defun python-shell-send-this-file()
  "send the file in buffer to python shell"
  (interactive)
  (python-shell-send-file (buffer-file-name))
  (define-key python-mode-map (kbd "C-c C-f") 'python-shell-send-this-file))

定义了以上函数,每次在emacs的minibuffer里手工输入M-x python-shell-send-this-file,能正常将buffer里面的文件发送到python shell里去运行,但是,用快捷键C-c C-f却总是会在minibuffer中提示:Describe symbol: ,然后就停在这里。