Can nested JSON string parsing be supported？

Can nested JSON string parsing be supported？
example：
```
var data = `{
    "name": "John",
    "nested_json": "{\"age\": 25, \"city\": \"New York\"}"
}`

expression = jmespath.compile('nested_json | from_json_string(@).[age,city]')
// from_json_string(nested_json).[age,city]

var result = expression.search(data)
```
output:
["25","New York"]