python2.7: no such file or directory after brew upgrade python3

Question

After doing brew update and brew upgrade python3 , I've been having such as bad interpreter: /usr/local/opt/python/bin/python2.7: no such file or directory . eg:

⇒  mkvirtualenv --python=/usr/local/bin/python3 labrador

mkvirtualenv:78: /usr/local/bin/virtualenv: bad interpreter: /usr/local/opt/python/bin/python2.7: no such file or directory
write() failed: Bad file descriptor

Answer 1

There are two possibilities here.

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First, as of Homebrew 1.5 , the python3 recipe was renamed python , and the python recipe is now available as python@2 . See the current docs on how things are organized.

While brew tries to make this just work like magic, if you had a really old install, or just a really complicated setup, with both python and python3 from Homebrew, and you brew upgrade python3 , you can end up with only the new (3.x) python recipe where you expect it to be.

To fix this one:

brew install python@2

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Second, you may have had a virtualenv installed into a non-Homebrew Python that's confused about where to find things.

The easiest fix here is to uninstall that virtualenv and pip install it with the Homebrew 3.x Python.

More generally, if you have other Python versions besides Homebrew 3.7, Homebrew 2.7, and Apple pre-installed 2.7, unless you have a good reason to need them, you might want to scrap them. And also, if you've installed any other Python packages into Apple's 2.7, you might want to uninstall those and make sure to never touch the Apple install and only use the Homebrew 2.7.

Or, if you do need lots of Python installs around, you should get used to running tools with <specific-python> -m tool instead of just tool . It's hard to keep all the different script and symlinks in sync, and way too easy to end up using a pip that you think matches python but actually installs into a completely different one, and a virtualenv that uses yet another one, and so on.

Answer 2

Solution in my case was:

pip uninstall virtualenv
pip install virtualenv

This was because, version of virtualenv and python were out of sync, but python and pip were still together:

$ virtualenv
-bash: /usr/local/bin/virtualenv: /usr/local/opt/python/bin/python2.7: bad interpreter: No such file or directory

$ python --version
Python 3.7.0

$ pip --version
pip 10.0.1 from /usr/local/lib/python3.7/site-packages/pip (python 3.7)

Both python and pip are 3.7, but virtualenv expected 2.7.

Un and Reinstall using pip (which expected 3.7) resulted in a virtualenv in the same version.

Answer 3

尝试了一些不起作用的事情..在我的情况下，这是有效的：

cd /usr/local/opt/python/bin/ ln -nfs /usr/local/Cellar/python@2/2.7.15_1/Frameworks/Python.framework/Versions/2.7/bin/python python2.7

Answer 4

I had a similar issue:

pre-commit is not in your $PATH; setting one up for you
Using virtualenv: /Users/jwilliams/.indy/venvs/pre-commit-venv_macosx-10.13-x86-64_cp2.7
$ cd /Users/jwilliams/repos/terraform-aws; /Users/jwilliams/.indy/venvs/pre-commit-venv_macosx-10.13-x86-64_cp2.7/bin/pre-commit install -f --install-hooks
dyld: Library not loaded: @executable_path/../.Python
  Referenced from: /Users/jwilliams/.indy/venvs/pre-commit-venv_macosx-10.13-x86-64_cp2.7/bin/python2.7
  Reason: image not found

$ cd /Users/jwilliams/repos/terraform-aws; /Users/jwilliams/.indy/venvs/pre-commit-venv_macosx-10.13-x86-64_cp2.7/bin/pre-commit install -f --install-hooks --hook-type pre-push
dyld: Library not loaded: @executable_path/../.Python
  Referenced from: /Users/jwilliams/.indy/venvs/pre-commit-venv_macosx-10.13-x86-64_cp2.7/bin/python2.7
  Reason: image not found

I followed the above steps and got the same error. The fix in my case was to delete the ~/.indy directory , and this forced indy to rebuild symlinks.