I have a data in a single object as json-format: 

```
var a = {
    "1": "alpha",
    "2": "beta",
    "3": "ceta"
}

```

I want to convert it into the following format: 

```
var b = [
    {id: 1, label: "alpha"},
    {id: 2, label: "beta"},
    {id: 3, label: "ceta"}
];

```

Can someone suggest a way to do this?