example script didn't work?
```javascript
var sketch = context.api()

log(sketch.api_version)
log(sketch.version)
log(sketch.build)
log(sketch.full_version)

var document = sketch.frontDocument;
var selection = document.selection;
var page = document.selectedPage;

var group = page.newGroup({frame:sketch.rectangle(0, 0, 100, 100), name:"Test"});
var rect = group.newShape({frame:sketch.rectangle(10, 10, 80, 80)});

log(selection.is_empty());
selection.iterate(function(item) { log(item.name); } );

selection.clear();
log(selection.is_empty());

group.select();
rect.add_to_selection();

sketch.input("Test", "default");
sketch.select("Test", ["One", "Two"], 1);
sketch.message("Hello mum!");
sketch.alert("Title", "message");
```



we got this error



```
1.1
40
33762
40 (33762)
TypeError: undefined is not an object (evaluating 'document.selection')
line: 15
sourceURL: /Users/tcmac/.atom/packages/sketchapp-scripter/scripting/run.sketchplugin
column: 25
stack: onRun@/Users/tcmac/.atom/packages/sketchapp-scripter/scripting/run.sketchplugin:15:25
```

and the `page.addGroup` seems didn't work too