opencv dmake issue

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####### opencv install ###########
##################################
## from  http://www.pyimagesearch.com/2016/10/24/ubuntu-16-04-how-to-install-opencv/
sudo apt-get install -y build-essential cmake pkg-config
sudo apt-get install -y libjpeg8-dev libtiff5-dev libjasper-dev libpng12-dev
sudo apt-get install -y libavcodec-dev libavformat-dev libswscale-dev libv4l-dev
sudo apt-get install -y libxvidcore-dev libx264-dev
sudo apt-get install -y libgtk-3-dev
sudo apt-get install -y libatlas-base-dev gfortran
sudo apt-get install -y python2.7-dev python3.5-dev
########## download opencv #######
cd ~
wget -O opencv.zip https://github.com/Itseez/opencv/archive/3.2.0.zip
unzip opencv.zip
wget -O opencv_contrib.zip https://github.com/Itseez/opencv_contrib/archive/3.2.0.zip
unzip opencv_contrib.zip
##### virtual environment and pip #######
cd ~
wget https://bootstrap.pypa.io/get-pip.py
sudo python get-pip.py
sudo pip install virtualenv virtualenvwrapper
sudo rm -rf ~/get-pip.py ~/.cache/pip
#### virtualenv and virtualenvwrapper
export WORKON_HOME=$HOME/.virtualenvs
source /usr/local/bin/virtualenvwrapper.sh
##### append to bashrc file. Only do this once.
echo -e "\n# virtualenv and virtualenvwrapper" >> ~/.bashrc
echo "export WORKON_HOME=$HOME/.virtualenvs" >> ~/.bashrc
echo "source /usr/local/bin/virtualenvwrapper.sh" >> ~/.bashrc
source ~/.bashrc
# mkvirtualenv cv --always-copy --python=python3.5  #this copies files over
mkvirtualenv cv -p python3   # this symlinks the files
pip install numpy
###### install opencv in the cv virtual environment ######
#workon cv
cd ~/opencv-3.2.0/
mkdir build
cd build
cmake -DCMAKE_BUILD_TYPE=RELEASE \
    -DCMAKE_INSTALL_PREFIX=/usr/local \
    -DINSTALL_PYTHON_EXAMPLES=ON \
    -DINSTALL_C_EXAMPLES=OFF \
    -DOPENCV_EXTRA_MODULES_PATH=~/opencv_contrib-3.2.0/modules \
    -DPYTHON_EXECUTABLE=~/.virtualenvs/cv/bin/python \
    -DBUILD_EXAMPLES=ON ..
make -j4
sudo make install
sudo ldconfig
cd /usr/local/lib/python3.5/site-packages/
sudo mv cv2.cpython-35m-x86_64-linux-gnu.so cv2.so
cd ~/.virtualenvs/cv/lib/python3.5/site-packages/
ln -s /usr/local/lib/python3.5/site-packages/cv2.so cv2.so
cd ~
rm -rf opencv-3.2.0 opencv_contrib-3.2.0 opencv.zip opencv_contrib.zip