# Trellis does not yet support Python 3.6.4

**URL:** https://discourse.roots.io/t/trellis-does-not-yet-support-python-3-6-4/13369
**Category:** trellis
**Tags:** ansible
**Created:** 2018-08-18T18:44:55Z
**Posts:** 11
**Showing post:** 10 of 11

## Post 10 by @mZoo — 2020-08-11T02:14:02Z

For those who need to do something in an old trellis install (and don’t want to deal with [updating it](https://discourse.roots.io/t/best-practices-to-update-trellis/5386)), on OS X, Python 2.7 can be [installed via Homebrew](https://stackoverflow.com/a/60345962/2223106) with:

```
brew install https://raw.githubusercontent.com/Homebrew/homebrew-core/86a44a0a552c673a05f11018459c9f5faae3becc/Formula/python@2.rb
```

(NOTE: Scott suggests, [here](https://discourse.roots.io/t/best-practice-for-upgrading-trellis/14377/2), that provisioning a new server as a good practice, when there have been significant (“breaking”) changes, such as upgrades to php.)

If `source /usr/local/bin/virtualenvwrapper.sh` script is returning an error:

```
Usage:   
  pip <command> [options]

no such option: -m
virtualenvwrapper.sh: There was a problem running the initialization hooks.

If Python could not import the module virtualenvwrapper.hook_loader,
check that virtualenvwrapper has been installed for
VIRTUALENVWRAPPER_PYTHON=/usr/local/bin/pip and that PATH is
set properly.
```

Fix is to add the following line to `/.bashrc` (or `.bash_profile`), before setting the `VIRTUALENVWRAPPER_PYTHON` variable::

```
export VIRTUALENVWRAPPER_PYTHON=/usr/local/bin/python # for brew installed python
```

I’m not sure what the best way to figure out which version of Ansible you need for your version of Trellis is. If it’s too old, Trellis will tell you. I guess you can also look at `trellis/plugins/vars/version.py` and see what `version_requirement` is.

---

_[View the full topic](https://discourse.roots.io/t/trellis-does-not-yet-support-python-3-6-4/13369)._