anchor.diff:  
   (defun execute-input (point string)
     (declare (ignore point))
  +  (unless (alive-process-p)
  +    (editor-error "Python process doesn't exist."))
     (lem-process:process-send-input *process*
                                     (concatenate 'string string (string #\newline))))
   
  
positive.code: 
  (defun get-repl-buffer ()
    (let ((buffer (make-buffer "*python*")))
      (change-buffer-mode buffer 'run-python-mode)
      buffer))
  
  (defun output-callback (string)
  
negative.code: 
  (defun run-python-internal ()
    (unless (alive-process-p)
      (when *process*
        (lem-process:delete-process *process*))
      (setf *process*
            (lem-process:run-process *python-run-command*
                                     :name "run-python"
                                     :output-callback 'output-callback))))
  
  (define-command python-eval-region (start end) ("r")
    (unless (alive-process-p)
      (editor-error "Python process doesn't exist."))
    (lem-process:process-send-input *process* (points-to-string start end)))
  
  (define-command run-python () ()
    (run-python-internal))
  
  (add-hook *exit-editor-hook*
            (lambda ()
              (when *process*
                (lem-process:delete-process *process*))))
  