{
   description = "Geospatial extent expressed in a particular CRS",
   fields = [
      {"br", {
         description = "Bottom right coordinates of the extent in CRS units"
      }},
      {"crs", {
         description = "CRS in which the extent is defined"
      }},
      {"tl", {
         description = "Top left coordinates of the extent in CRS units"
      }}
   ]
}
