OpenCV 3.1.0 Face module built , can't import in Python

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I cmaked OpenCV 3.1.0 with success and then cmaked extras:

cmake -D CMAKE_BUILD_TYPE=RELEASE   -D CMAKE_INSTALL_PREFIX=/usr/local -D     BUILD_PYTHON_SUPPORT=ON ..
cmake -D OPENCV_EXTRA_MODULES_PATH=../../opencv_contrib/modules ..
sudo make
sudo make install
sudo ldconfig

I think Face module is OK also:

$~/opencv/build/lib$ ls libopencv_face.so*
libopencv_face.so  libopencv_face.so.3.1  libopencv_face.so.3.1.0

/usr/local/lib$ ls libopencv_face*
libopencv_face.so  libopencv_face.so.3.1  libopencv_face.so.3.1.0

However, I can't import Face module in Python:

>>> import cv2
>>> cv2.face
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: 'module' object has no attribute 'face'

Thanks in advance.