I am new to Linux and Raspberry Pi, so sorry if this is some trivial question or if I did not mention some important information.
To my problem:
I have a fresh install of Raspbian Stretch on a Raspberry Pi 3B+ and want to install OpenCV on it. For this, I am following this tutorial: https://www.pyimagesearch.com/2017/09/04/raspbian-stretch-install-opencv-3-python-on-your-raspberry-pi/
Within this tutorial, it is also recommended to use virtual environments for programming in python. Therefore, the packages 'virtualenv' and 'virtualenvwrapper' are installed. However, once I enter the command 'sudo pip install virtualenv virtualenvwrapper', I get the following error message:
ERROR: Package 'stevedore' requires a different Python: 3.5.3 not in '>=3.6'
The first thing I tried to solve the problem was to upgrade Python to a higher version. So now the command 'python3 --version' returns '3.6.9'. However, this did not help and the error persisted. I also tried using pip3 within the command but then I get the following message 'pip is configured with locations that require TLS/SSL, however the ssl module in Python is not available.' which then let to a different error. I also tried downloading the package directly from https://www.piwheels.org/ but without success.
Does anyone have an idea how to solve this issue? Thanks in advance.