# download a page
def download_page(urlstr):
    ret = os.system("wget -O temp.html \"" + urlstr + "\"")
    if ret != 0:
        raise Exception("wget")
    fd = open("temp.html", "rb")
    page = fd.read()
    fd.close()
    print("type of page = " + str(type(page)))
    if type(page) != str:
        page = str(page)
    return page