warp_mouse()
This doesn't seem to work for me on Linux. I have 

`pyxel.init(320, 200, fps = 60, quit_key = py.KEY_ESCAPE)`

but warp_mouse (160, 100) doesn't put the cursor at screen centre - if that's what it's supposed to do? It looks as if it's placing it at window pixel (160, 100) instead ie using screen resolution.