So I trying out the Mix IDE (1.03), and looking at the .html file from the sample project, there is a "contracts" global. Where is it defined?

function get() { var param = document.getElementById('query').value; var res = contracts['Sample'].contract.get(); document.getElementById('queryres').innerText = res; } function set() { var key = document.getElementById('key').value; var res = contracts['Sample'].contract.set(key); }