Poetry add package Permission Denied

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• I have searched the documentation and believe that my question is not covered.

Question

When I try to add a new package, poetry tries to access root folders and a ‘Permission denied’ error is thrown:

$ poetry add tldextract
Using version ^2.2 for tldextract

Updating dependencies
Resolving dependencies... (0.6s)


Package operations: 8 installs, 1 update, 5 removals

Writing lock file

 - Updating six (1.10.0 -> 1.11.0)
                                                                                                                                                      
[EnvCommandError]                                                                                                                       
Command ['pip', 'install', '--no-deps', '-U', 'six==1.11.0'] errored with the following output:                                                      
Collecting six==1.11.0                                                                                                                               
 Using cached https://files.pythonhosted.org/packages/67/4b/141a581104b1f6397bfa78ac9d43d8ad29a7ca43ea90a2d863fe3056e86a/six-1.11.0-py2.py3-none-a  
ny.whl                                                                                                                                               
Installing collected packages: six                                                                                                                   
 Found existing installation: six 1.10.0                                                                                                            
   Uninstalling six-1.10.0:                                                                                                                         
Could not install packages due to an EnvironmentError: [Errno 13] Permission denied: '/usr/lib/python3/dist-packages/__pycache__/six.cpython-35.pyc

It tries to update a package that is installed as the root user and fails when uninstalling the old version.

Does poetry not create its own virtual environment to manage the dependencies? I assumed it would never try access any root folder.

Also, when I run poetry shell command, it looks like it is using virtualenv, but I cannot run any command in it:

$ poetry shell
Spawning shell within /home/$USER/.cache/pypoetry/virtualenvs/my-package-py3.5

$ poetry add tldextract
[ImportError]
No module named 'pkg_resources'

I assume something is wrong with my setup, but I could not pinpoint where the problem is. Any help is greatly appreciated.

Thanks

$ python --version
Python 3.5.3

$ pip --version
pip 18.1 from /usr/local/lib/python3.5/dist-packages/pip (python 3.5)

$ poetry --version
Poetry 0.12.7