code: def save(self, target=None, shp=None, shx=None, dbf=None):
          
          # TODO: Create a unique filename for target if None.
          if shp:
              self.saveShp(shp)
          if shx:
              self.saveShx(shx)
          if dbf:
              self.saveDbf(dbf)
          elif target:
              self.saveShp(target)
              self.shp.close()
              self.saveShx(target)
              self.shx.close()
              self.saveDbf(target)
              self.dbf.close()
docs: Save the shapefile data to three files or
          three file-like objects. SHP and DBF files can also
          be written exclusively using saveShp, saveShx, and saveDbf respectively.