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### Using python virtual environment for ROS2 on windows

It seems that the installation procedure of ROS2 under windows is depending on a python installation in C:\Python37. (As a side node, the recommended "choco install -y python" now installs python 3.8, which is not intended).

I was following the procedure mentioned here https://index.ros.org/doc/ros2/Installation/Dashing/Windows-Install-Binary/ to install dashing ROS2 on windows. I found out that the ROS2 distribution has a hardcoded dependency on a python 3.7 installation in C:\Python37.

Because we are using python for different projects which may involve or not involve ROS2, I would like to use a python virtual environment for ROS2. However, it seems that this is not supported, because the scripts using the hardcoded shebang

#!c:\python37\python.exe


Even when placing the virtual environment in C:\Python37, the shebang is incorrect, because python would be in

#!c:\python37\Scripts\python.exe


instead. So I am getting errors like "failed to create process" when running ros2. Using "python ros2-script.py" instead works though (assuming an activated virtual environment). Changing the shebang would work in principle, but which scripts should I change?

Is it planned to have an installer in the future who cares about these things?