Bdtyktl

I installed Python, pip3, and virtualenv as in this guide for TensorFlow:

brew install python

pip3 install -U virtualenv

Then I was able to create a virtual environment with:

virtualenv --system-site-packages -p python3 ./venv

Then I tried installing TensorFlow with

pip install --upgrade tensorflow

but it failed because TensorFlow is not yet compatible with Python 3.7. So I removed Python 3.7 with brew remove python and installed 3.6.7 from an installer. But running the same virtualenv command now fails:

$ virtualenv --system-site-packages -p python3 ./venv

-bash: /usr/local/bin/virtualenv: /usr/local/opt/python/bin/python3.7: bad interpreter: No such file or directory

$ which python3

/Library/Frameworks/Python.framework/Versions/3.6/bin/python3

So the virtualenv link to the executable lists the newest Python version, even after removal.

Furthermore, virtualenv lists brew as the user group, which is also confusing:

$ ls -la /usr/local/bin/virtualenv

-rwxr-xr-x  1 user  brew  232 29 Nov 17:06 /usr/local/bin/virtualenv

I've tried uninstalling virtualenv with both pip and pip3 and I get:

Skipping virtualenv as it is not installed.

How can I fix this issue?

After a few hours, one solution was to install virtualenv again with pip, then remove it with pip:

$ ls -la /usr/local/bin/virtualenv

-rwxr-xr-x  1 user  brew  232 29 Nov 17:06 /usr/local/bin/virtualenv

$ pip install virtualenv

...

$ pip uninstall virtualenv

...

$ which virtualenv

$ ls -la /usr/local/bin/virtualenv

ls: /usr/local/bin/virtualenv: No such file or directory

And then install it again with pip3:

$ pip3 install virtualenv

Collecting virtualenv

...

Installing collected packages: virtualenv

Successfully installed virtualenv-16.1.0

Notice the use of pip3, and not pip, unlike this link, pointed to by TensorFlow.

And now creating the virtual environment works:

$ virtualenv --system-site-packages -p python3 ./venv

Running virtualenv with interpreter /Library/Frameworks/Python.framework/Versions/3.6/bin/python3

Using base prefix '/Library/Frameworks/Python.framework/Versions/3.6'

New python executable in ~/venv/bin/python3

Also creating executable in ~/venv/bin/python

Installing setuptools, pip, wheel...

done.