https://developers.weixin.qq.com/miniprogram/dev/OpenApiDoc/

大佬们请问

"thumb_fileid": "306c0201020465306302010002044675d9d102031e90380204e7de892b020467347b8e0435313138323132383539335f3832393831333635375f3562373930303432393933661028000203025b6004000201010201000400",

"hex_aes_key": "68747673676F68796A69",

"md5": "5b790042993f5afbc142f806d",

这个微信小程序封面的参数，要怎么创建啊？