from mapnik import Map, Layer
proj4 = '+proj=tmerc +lat_0=41.08333333333334 +lon_0=-71.5 +k=0.99999375 +x_0=100000 +y_0=0 +ellps=GRS80 +units=m +no_defs'
m = Map(256,256,proj4)
lyr = Layer('Name',proj4)