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;; Interactive functions to hexify and unhexify urls
(defun hexify-region (start end)
  (interactive "r")
  (let ((hex-string (url-hexify-string 
		   (filter-buffer-substring start end))))
    (delete-region start end)
    (insert hex-string)))

(defun unhexify-region (start end)
  (interactive "r")
  (let ((hex-string (url-unhex-string 
		   (filter-buffer-substring start end))))
    (delete-region start end)
    (insert hex-string)))