proj4 = '+proj=utm +zone=18 +ellps=intl +towgs84=-806.413,-263.5,-622.671,6.018583e-05,-1.450001e-05,-0.0001892455,-20.81616 +units=m +no_defs +type=crs'
m = Map(256,256,proj4)
lyr = Layer('Name',proj4)