modis - Getting 16 days composite in Google Earth Engine?

I've wrote this code. In this code I've call lst daily product. But I don't know how can I compute 16 days mean composite from daily product?

code link: https://code.earthengine.google.com/b29845b2c97b13074c7b370cd8a0460f

Map.centerObject(table);
Map.addLayer(table);

var modis = ee.ImageCollection('MODIS/006/MOD11A1')
.filterBounds(table)
.filterDate('2010-01-01','2011-01-01');

Answer

https://code.earthengine.google.com/51693fbc41dc7ecad81e930079fc1a5b

PS: I did not come up with this code, but rather found it myself when I needed it for monthly collection.