<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def unconvert_coord_object(tile):
 """Convert rawr_tiles.tile.Tile -> ModestMaps.Core.Coordinate"""

    assert isinstance(tile, Tile)
    return Coordinate(zoom=tile.z, column=tile.x, row=tile.y)