例外タイプ:ValueError例外値:
ビューcanvas.views.pdfDirectoryはHttpResponseオブジェクトを返しませんでした。
例外の場所:get_responseの129行目の/usr/local/lib/python2.6/dist-packages/Django-1.4.3-py2.6.egg/django/core/handlers/base.py
import os
from reportlab.pdfgen import canvas
from reportlab.lib.pagesizes import letter
from reportlab.lib.units import cm, mm, inch, pica
def pdfDirectory(imageDirectory, outputPDFName = 'ima.pdf'):
    dirim = str(imageDirectory)
    output = str(outputPDFName)
    width, height = letter
    height, width = letter
    c = canvas.Canvas(output, pagesize=letter)
    # try:
    for root, dirs, files in os.walk(dirim):
        for name in files:
            lname = name.lower()
            if lname.endswith(".JPG") or lname.endswith(".gif") or      lname.endswith(".png"):
                filepath = os.path.join('/home/deepak/Downloads', 'image')
                c.drawImage('/home/deepak/Downloads/imag.pdf', inch, inch * 1)
                c.showPage()
                c.save()
                return output
    #   print "PDF of Image directory created"
    # except:
    #  print "Failed creating PDF"