只返回media_id ,没有其他参数返回是什么原因？

https://developers.weixin.qq.com/miniprogram/dev/platform-capabilities/business-capabilities/ministore/minishopopencomponent2/API/public/upload_img.html

入参和请求
files = {
    'upload_type': 3,
    'resp_type': 3,
    'img_url': 'https://cdn-qn.huaeb.com/sellmall/20201107/FjROhuDy-_hcvFCmHNsIl-ms3Mgo.jpg'
}
res =  requests.post('https://api.weixin.qq.com/shop/img/upload?access_token=', files=files).json()
返回参数{u'img_info': {u'temp_img_url': u'', u'media_id': u'wxashop_OPpHdjXhLUJEkgfHz46Q4Q50AIRwmwoNuRwTLc/+AZFC3i6fF2Hh0zz+gyirOZHKSEDkD3Q6lvhTB6437AHymw==', u'pay_media_id': u''}, u'errcode': 0}