Splits a PDF file for manual double-side printing

splitpdf.py

#!/usr/bin/env python3

import sys, os
from PyPDF2 import PdfFileReader, PdfFileWriter

inputname = sys.argv[1]
pdf = PdfFileReader(inputname)
numpages = pdf.getNumPages()
if numpages % 2 == 1:
    numpages = numpages - 1
    pdf_writer = PdfFileWriter()
    pdf_writer.addPage(pdf.getPage(numpages))
    with open("last.pdf", "wb") as out:
        pdf_writer.write(out)

odd = PdfFileWriter()
even = PdfFileWriter()
for i in range(numpages):
    page = pdf.getPage(i)
    if (i % 2) == 1:
        odd.addPage(page)
    else:
        even.addPage(page)

with open("odd.pdf", "wb") as out:
    odd.write(out)

with open("even.pdf", "wb") as out:
    even.write(out)