import Rhino
import scriptcontext as sc
import System.Drawing
import rhinoscriptsyntax as rs
# create a new PDF document
pdf = Rhino.FileIO.FilePdf.Create()
dpi = 300
size = System.Drawing.Size(8.5*dpi,11*dpi)
settings = Rhino.Display.ViewCaptureSettings(sc.doc.Views.ActiveView, size, dpi)
# add 1 or more pages based on ViewCaptureSettings
pdf.AddPage(settings)
#write the pdf file to disk
filename = rs.SaveFileName()
pdf.Write(filename)