请回答数字3到7的平方，并以JSON格式输出结果。
user
```json
{
  "numbers": [
    {
      "number": 3,
      "square": 9
    },
    {
      "number": 4,
      "square": 16
    },
    {
      "number": 5,
      "square": 25
    },
    {
      "number": 6,
      "square": 36
    },
    {
      "number": 7,
      "square": 49
    }
  ]
}
```
assistant