Path: /ip/open-api/proxy-buy
Method: POST
Interface description: Purchase proxy
Parameter description:
| Parameter name | Is it necessary | Example | Remarks | Usage scenarios | 
| days | Yes | 30 | Number of days (supports 30, 90, 180, 360) | |
| area_id | Yes | 239 | Region ID | |
| auto_extend | Yes | 1 | Auto-renewal 0 off 1 on | |
| num | Yes | 1 | Quantity <= 100 | 
Return data:
{
  "data": {
    "order_id": "g1k29a2"
  },
  "code": 0,
  "msg": "Success"
}
Field description:
| order_id | Order ID | 
