获取钉钉开发access_token

def access_token():
    p1="data/dingtalk/token.txt"
    b1=True#是否请求token
    re=""
    if os.path.exists(p1):
        r=txtread(p1)
        a1=json.loads(r)
        t1=a1["time"]
        tk=a1["access_token"]
        if t1<int(time.time()):
            b1=True
        else:
            b1=False
            re=tk
    #b1为true 请求更新token 
    if b1:
        print("正在获取token")
　　　　　#
        app_key="####"
　　　　　#
        app_secret="###"
　　　　 #
        url="https://oapi.dingtalk.com/gettoken?appkey={0}&appsecret={1}".format(app_key,app_secret)
        r=requests.get(url)
        a1=json.loads(r.text)
        tk=a1["access_token"]
        t1=int(time.time())+7000
        a2={"access_token":tk,"time":t1}
        txtwrite(p1,json.dumps(a2))
        re=tk
    return re