Issue when creating a python package that uses unified-planning inside a virtual environment.

[MFaisalZaki]

I'm developing a planner Python module. The module works fine when I install it using python setup.py install --user. However, when I install the module inside a virtual environment, it throws a permission denied error.

To Reproduce To make it easy to reproduce, download and unzip this package:

unzip issue.zip 
cd issue
python3 build-env.py
source venv-dir/bin/activate
python3 test-planner.py

The first script creates a virtual environment and installs the package. The second script runs symk inside another class. It is expected to receive a plan, and if we receive a None object, then it throws an assertion, "The seed plan is None"

It performed the preprocessing fine and generated the grounded predicates. However, it fails when trying to invoke downward executable.

UPDATE: This issue happens on Linux machines and works fine with MacOS.

[MFaisalZaki]

I'm sorry for reporting this. After more debugging I found out the problem came from my machine. I had unified-planning installed on the machine and not inside a virtual environment.