Comment by cv_new for I built the OpenCV4 by Cmake and installed the opecv4.0 using anaconda3 with its python 3.7 verison. My platform is Ubuntu 18.04 LTS. However, when testing the installation, I encounter the following problem:ype "help", "copyright", "credits" or "license" for more information. >>> import cv2 Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/home/user/anaconda3/lib/python3.7/site-packages/cv2/__init__.py", line 89, in <module> bootstrap() File "/home/user/anaconda3/lib/python3.7/site-packages/cv2/__init__.py", line 62, in bootstrap ], True) File "/home/user/anaconda3/lib/python3.7/site-packages/cv2/__init__.py", line 56, in load_first_config raise ImportError('OpenCV loader: missing configuration file: {}. Check OpenCV installation.'.format(fnames)) ImportError: OpenCV loader: missing configuration file: ['config-3.7.py', 'config-3.py']. Check OpenCV installation. >>> I typed the command:echo $PYTHONPATH I get:/home/user/anaconda3/lib/python3.7/site-packages Updated:I found that the /home/user/anaconda3/lib/python3.7/site-packages/cv2/ does not contain the config-3.7.py, but it contains config-3.6.py. At the beginning, I ensured that all python3 are correlated to the anaconda's python 3.7 library. I don't know why the cv2 folder still uses the Ubuntu's default python.I have tried deleting the cv2 folder and rebuild it again, but it still generates the config-3.6.py file. I don't know why it will like this. By the way, I didn't turn on the opencv python3 verison in Cmake config of building OpenCV, will it be affected?Please help. ThanksA part of Cmake is here: After modifying the Cmake config following the instruction from and removing python2 related setting , I clear the build folder and rebuilt again. I did pip3 install --upgrade, but the cv2 folder still contain the config-3.6.py.Second update:I have upgraded the Ubuntu's Python from 3.6 to 3.7 according to this tutorial ((http://ubuntuhandbook.org/index.php/2019/02/install-python-3-7-ubuntu-18-04/)) and run this command "sudo apt-get install python3.7-dev" . The above errors disappear and the command "import cv2" can run now. But I find some special pointing locations when installing OpenCV4.1. The python3 library used is User's library instead of Anaconda's. -- Python 2: -- Interpreter: (ver 2.7.15) -- Libraries: NO -- numpy: NO (Python wrappers can not be generated) -- install path: - -- -- Python 3: -- Interpreter: /home/user/anaconda3/bin/python3.7m (ver 3.7.5) -- Libraries: /usr/lib/x86_64-linux-gnu/libpython3.7m.so (ver 3.7.5) -- numpy: /home/user/anaconda3/lib/python3.7/site-packages/numpy/core/include (ver ) -- install path: /home/user/anaconda3/lib/python3.7/site-packages/cv2/python-3.7 -- -- Python (for build): /home/user/anaconda3/bin/python3.7m

According to your instruction, I have made the upgrade, then I corrected my Cmake config, and clean the build and rebuilt again. The same problem of missing configuration files appears again. It still generates a python 3.6 folder and config-3.6.py and some folders in /home/user/anaconda3/lib/python3.7/site-packages/cv2/ .