async def get_postpay_detail(ns={}):
    
    baidu_id = ns.get('baidu_id')
    pageno = int(ns.get('pageno'))
    # 获取当前日期和时间
    current_time = datetime.datetime.now()
    
    days_ago = current_time - datetime.timedelta(days=20)
    # 获取账单百度指定必须在同一个月内
    if current_time.month != days_ago.month:
        days_ago = datetime.datetime(current_time.year, current_time.month, 1)

    # 将日期时间格式化为字符串
    current_day = current_time.strftime("%Y-%m-%d")
    days_ago_time = days_ago.strftime("%Y-%m-%d")
    
    ns = {
        "beginTime": days_ago_time,
        "endTime": current_day,
        "queryAccountId" : baidu_id,
        "pageNo": pageno,
        "pageSize": 100
    }
    method = 'POST'
    ns_format = '&'.join(['%s=%s' % (k, v) for k, v in ns.items()])
    url = 'https://billing.baidubce.com/v1/bill/resource/chargeitem?%s' % ns_format
    header = {
        "Host": "billing.baidubce.com"
    }
    header = await get_auth_header(method=method, url=url, header=header)
    async with aiohttp_client.request(
                method=method,
                url=url,
                headers=header,
                json=ns) as res:
        data_bill = await res.json()
        return {
            'status': True,
            'data': data_bill
        }

ret = await get_postpay_detail(params_kw)
return ret