anchor.diff:  (defun refresh-classes ()
     "sets *classes* to an alist of (classname . classid) pairs"
     (let ((json (st-json:read-json 
  -	       (request-url *base-url*))))
  +	       (drakma:http-request *base-url*))))
       (setf *classes*
   	  (mapcar #'(lambda (item)
   		      (cons (st-json:getjso "name" item)
  
positive.code: (pushnew '("text" . "html") drakma:*text-content-types*)
  
  (defvar *classes*)
  (defparameter *cookie-jar*
    (make-instance 'drakma:cookie-jar
                   :cookies (list
  			   (make-instance 'drakma:cookie
  					  :name "schoolname"
  					  :value "\"_V2luZGVzaGVpbQ==\""
  					  :domain "roosters.windesheim.nl"))))
  
  (local-time:define-timezone 
      amsterdam 
  
negative.code:   (:documentation "Represents an instance of a lesson, mostly for when a
                     lesson is given to parts of a class separately"))
  
  (defun timestamp->datestring (timestamp)
    "Converts a timestamp to a `datestring`"
    (local-time:format-timestring NIL timestamp :format '((:year 4) (:month 2) (:day 2))))
  