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(defun header-encode (string)
  (if (find-if (lambda (c) (> (char-code c) 127)) string)
      (format nil "~{=?utf-8?B?~A?=~#[~:;~% ~]~}"
	      (cl-ppcre:split #\Newline
			      (cl-base64:usb8-array-to-base64-string
			       (portable-string-to-octets string)
			       :columns 40)))
      (format nil " ~A~%" string)))

(defun mail-headers (to from subject mime-type)
  (format nil "To: ~A
From: ~A
Subject:~AContent-Type: ~A;charset=utf-8
" to from (header-encode subject) mime-type))

(defun better-mail-headers (to from subject mime-type)
  (format nil "To: ~A
From: ~A
Subject: ~A
Content-Type: ~A;charset=utf-8
" to from (header-encode subject) mime-type))