Python - Unable to detect face and eye?

I am trying to create a face and eye detection using OpenCV library. This is the code I been working with. It's running smoothly with no errors but the only problem is not showing any results no faces and eyes are found with this code

import cv2
import sys
import numpy as np
import os

# Get user supplied values
imagePath = sys.argv[1]


# Create the haar cascade
faceCascade = cv2.CascadeClassifier('C:\Users\Karthik\Downloads\Programs\opencv\sources\data\haarcascades\haarcascad_frontalface_default.xml')
eyeCascade= cv2.CascadeClassifier('C:\Users\Karthik\Downloads\Programs\opencv\sources\data\haarcascades\haarcascade_eye.xml')

# Read the image
image = cv2.imread(imagePath)
gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)

# Detect faces in the image
faces = faceCascade.detectMultiScale(
    gray,
    scaleFactor=1.2,
    minNeighbors=5,
    minSize=(30, 30),
    flags = cv2.cv.CV_HAAR_SCALE_IMAGE
)

print "Found {0} faces!".format(len(faces))

# Draw a rectangle around the faces
for (x, y, w, h) in faces:
    cv2.rectangle(image, (x, y), (x+w, y+h), (255, 0, 0), 2)
    roi_gray = gray[y:y+h, x:x+w]
    roi_color = image[y:y+h, x:x+w]

    eyes = eyeCascade.detectMultiscale(roi_gray)
    for (ex,ey,ew,eh) in eyes:
            cv2.rectangle(roi_color,(ex,ey),(ex+ew,ey+eh),(0, 255, 0), 2)


cv2.imshow("Faces found", image)
print image.shape
cv2.waitKey(0)

For me it works in my jupyter notebook on Ubuntu 15.10 using OpenCV 3.1.0-dev with python 3.4

Could it be, that you have a simple typo?

haarcascad_frontalface_default.xml => haarcascade_frontalface_default.xml

and here:

eyes = eyeCascade.detectMultiscale(roi_gray) => eyeCascade.detectMultiScale(roi_gray)

That's my working code:

%matplotlib inline

import matplotlib
import matplotlib.pyplot as plt

import cv2
import sys
import numpy as np
import os

# Create the haar cascade
faceCascade = cv2.CascadeClassifier('haarcascade_frontalface_default.xml')
eyeCascade= cv2.CascadeClassifier('haarcascade_eye.xml')

# Read the image
image = cv2.imread('lena.png', 0)

if image is None:
    raise ValueError('Image not found')

# Detect faces in the image
faces = faceCascade.detectMultiScale(image)

print('Found {} faces!'.format(len(faces)))

# Draw a rectangle around the faces
for (x, y, w, h) in faces:
    cv2.rectangle(image, (x, y), (x+w, y+h), 255, 2)
    roi = image[y:y+h, x:x+w]

    eyes = eyeCascade.detectMultiScale(roi)
    for (ex,ey,ew,eh) in eyes:
            cv2.rectangle(roi,(ex,ey),(ex+ew,ey+eh), 255, 2)


plt.figure()
plt.imshow(image, cmap='gray')
plt.show()