docs: def unregister_course (self, course_id):
          """ 履修申請を取り消す """
          course_id = course_id.upper()
  
          # 何モジュール開講か取得
          kdb = twins.kdb.Kdb()
          first_module = kdb.get_course_info(course_id)["modules"][:2]
          if not first_module.startswith("春") and \
             not first_module.startswith("秋"):
              raise RequestError()
          module_code, gakkiKbnCode = {
                                        "春A": (1, "A"),
                                        "春B": (2, "A"),
                                        "春C": (3, "A"),
                                        "秋A": (4, "B"),
                                        "秋B": (5, "B"),
                                        "秋C": (6, "B")
                                      }.get(first_module)
  
          # 履修登録照会画面から時限、曜日とかを取り出す
          courses = {}
          self.req("RSW0001000-flow")
          r = self.get({
                         "_eventId":   "search",
                         "moduleCode": module_code,
                         "gakkiKbnCode": gakkiKbnCode
                       })
  
          for js_args in re.findall("DeleteCallA\(([\'\ \,A-Z0-9]+)\)", r.text):
              js_args = js_args.replace("'", "").split(",")
              if js_args[2] in courses:
                  continue  # 1-2限,2-3限など、連続してあるやつ
              courses[js_args[2]] = {
                                      "yobi":  js_args[3],
                                      "jigen": js_args[4],
                                      "nendo": js_args[0],
                                      "jikanwariShozokuCode": js_args[1]
                                    }
  
          if course_id not in courses:
              raise RequestError()
  
          r = self.post({
                          "_eventId": "delete",
                          "yobi":     courses[course_id]["yobi"],
                          "jigen":    courses[course_id]["jigen"],
                          "nendo":    courses[course_id]["nendo"],
                          "jikanwariShozokuCode": courses[course_id]
                                                    ["jikanwariShozokuCode"],
                          "jikanwariCode": course_id,
                        }, True)
  
          r = self.post({"_eventId": "delete"}, True)
  
          errmsg = pq(r.text)(".error").text()
          if errmsg != "":
              raise RequestError()