请列举出所有月份的英文名，并用它们的缩写格式表示。
user
```json
{
  "月份": [
    {"一月": "Jan."},
    {"二月": "Feb."},
    {"三月": "Mar."},
    {"四月": "Apr."},
    {"五月": "May"},
    {"六月": "Jun."},
    {"七月": "Jul."},
    {"八月": "Aug."},
    {"九月": "Sep."},
    {"十月": "Oct."},
    {"十一月": "Nov."},
    {"十二月": "Dec."}
  ]
}
```
assistant