Deletes a Wharton GSR Booking for a given booking and session id.

def delete_booking(self, sessionid, booking_id):
        """ Deletes a Wharton GSR Booking for a given booking and session id. """
        url = "{}{}{}/".format(BASE_URL, "/delete/", booking_id)
        cookies = dict(sessionid=sessionid)

        try:
            resp = requests.get(url, cookies=cookies, headers={'Referer': '{}{}'.format(BASE_URL, "/reservations/")})
        except resp.exceptions.HTTPError as error:
            raise APIError("Server Error: {}".format(error))

        if resp.status_code == 404:
            raise APIError("Booking could not be found on server.")

        html = resp.content.decode("utf8")
        if "https://weblogin.pennkey.upenn.edu" in html:
            raise APIError("Wharton Auth Failed. Session ID is not valid.")

        resp.raise_for_status()

        soup = BeautifulSoup(html, "html5lib")
        middleware_token = soup.find("input", {'name': "csrfmiddlewaretoken"}).get('value')

        csrftoken = resp.cookies['csrftoken']
        cookies2 = {'sessionid': sessionid, 'csrftoken': csrftoken}
        headers = {'Referer': url}
        payload = {'csrfmiddlewaretoken': middleware_token}

        try:
            resp2 = requests.post(url, cookies=cookies2, data=payload, headers=headers)
        except resp2.exceptions.HTTPError as error:
            raise APIError("Server Error: {}".format(error))

        return {"success": True}