<p>How do you update a summary field's value from post function in JIRA?</p>

Ok, I'll try to explain... For simplicity, suppose we have a post function and we want summary value changed to "foobar":
```
```
public class SomePostFunction implements FunctionProvider {

    public void execute(Map transientVars, Map args, PropertySet ps) throws WorkflowException {
        String newValue = "foobar";
        // TODO update summary so it's value becomes newValue
    }

}
```
```