Setting up and using Python3 Virtualenv on Mac

Python3 Virtualenv Setup.md

Python3 Virtualenv Setup

Requirements

• Python 3
• Pip 3

$ brew install python3

Pip3 is installed with Python3

Installation

To install virtualenv via pip run:

$ pip3 install virtualenv

Usage

Creation of virtualenv:

$ virtualenv -p python3 <desired-path>

Activate the virtualenv:

$ source <desired-path>/bin/activate

Deactivate the virtualenv:

$ deactivate

About Virtualenv

@raitisd: Well, that's the idea.

For some reason, brew recently decided that python refers to python3 instead of python2.
It's a pain in the ass.

Here, I wrote you a little script:

brew uninstall --force --ignore-dependencies python python2 python2.7 python3 python3.6 > /dev/null 2>&1
brew install python@2 python@3 > /dev/null 2>&1
echo; for x in python python2 python3; do 
which $x; readlink $(which $x); $x --version; echo; done

The output should look like this:

/usr/local/bin/python
../Cellar/python@2/2.7.14_3/bin/python
Python 2.7.14

/usr/local/bin/python2
../Cellar/python@2/2.7.14_3/bin/python2
Python 2.7.14

/usr/local/bin/python3
../Cellar/python/3.6.4_4/bin/python3
Python 3.6.4

If it does, it should be fixed.

The copy of python that belongs to the OS still lives here: /usr/bin/python

@tjt263 thank you, worked like a charm!

@tjt263 thanks!

Well I tried this and it doesn't work for me. It fails here:

$ virtualenv -p python3 venv
-bash: virtualenv: command not found

$ pip3 install virtualenv
Requirement already satisfied: virtualenv in /Users/enewhuis/Library/Python/3.6/lib/python/site-packages

I can add /Users/enewhuis/Library/Python/3.6/bin to my path but, as is, the instructions here didn't work.

This fails and doesn't recognize python 3.
I need to have python 2.7 and python 3 on my system.

I'm currently using virtualenvwrapper with 2.7. Is there a way to integrate python 3 to take advantage of virtualenvwrapper?
Thanks!

@rlam3 - you can install python3 independently from python on a Mac or PC. While I'm not a huge fan of non-native development (meaning I recommend developing on linux with vmware if you are deploying to a linux variant), you can still install python side by side.

It's would also be helpful if you mentioned your operating system, current file path, etc.... People want to help but we need details.

There is a course on udemy (google it as "learn-python-3-from-beginner-to-advanced" and you'll find it). I have no connection with them, but that course does a good job of getting you started with your development environment imho.

I had this problem Linking /usr/local/Cellar/python/3.7.1... Error: Permission denied @ dir_s_mkdir - /usr/local/Frameworks
and

sudo mkdir /usr/local/Frameworks
sudo chown $(whoami):admin /usr/local/Frameworks

solved it

if it fails for you in:
virtualenv -p python3 <desired_path>
Try:
python3 -m virtualenv <desired_path>

if it fails for you in:
virtualenv -p python3 <desired_path>
Try:
python3 -m virtualenv <desired_path>

This actually worked for me! thanks!

Anyone knows how to activate the virtualenv without having to remember the path to its directory? I'm talking about command similar to conda virtualenv.
conda activate <name-of-venv>

Thank you, this worked for me.

Thank you. It works!

Thanks! Every single time Homebrew does an update to Python I forget that the new version totally hoses up the venv (because I never deactivate it) so your page is very useful for me every couple of months.

Thanks, it worked perfectly!

Totally saved me after I had an issue with brew. Thank you!

Great and simple! Thank you!

Awesome, I needed to steal it as a Gist for future references. Thanks.
As a note, is common to use "venv" as the path/folder to store virtual env info. This is usually included within .gitignore files.

haven't used MacOS for a while. Saving this for the new laptop:)

@raitisd: Well, that's the idea.

For some reason, brew recently decided that python refers to python3 instead of python2.
It's a pain in the ass.

Here, I wrote you a little script:

brew uninstall --force --ignore-dependencies python python2 python2.7 python3 python3.6 > /dev/null 2>&1
brew install python@2 python@3 > /dev/null 2>&1
echo; for x in python python2 python3; do 
which $x; readlink $(which $x); $x --version; echo; done

The output should look like this:

/usr/local/bin/python
../Cellar/python@2/2.7.14_3/bin/python
Python 2.7.14

/usr/local/bin/python2
../Cellar/python@2/2.7.14_3/bin/python2
Python 2.7.14

/usr/local/bin/python3
../Cellar/python/3.6.4_4/bin/python3
Python 3.6.4

If it does, it should be fixed.

The copy of python that belongs to the OS still lives here: /usr/bin/python

I was getting this error **
RuntimeError: failed to find interpreter for Builtin discover of python_spec='python3'

AN ERROR OCCURRED

java.lang.IllegalStateException: Creating virtual env exited with 1. Check the logs for more details.
**

I am using MacOS, and python2.7 comes inbuilt. I was facing some issues while installing virtualenv, installed it with pip after some efforts. But now I think the conflict is due to the python versions (2.7 & 3). I do not have Python 3 installed in my system.
So I tried your script @tjt263, but got the below response **

/usr/bin/python
Python 2.7.10

-bash: python2: command not found

-bash: python3: command not found
**

Any idea what could possibly be the issue?

Youre awesomeeeee

Worked like a charm!

Thanks It worked

Just use pip in the venv. https://docs.python.org/3/library/venv.html

if it fails for you in:
virtualenv -p python3 <desired_path>
Try:
python3 -m virtualenv <desired_path>

If i use both of this i get this error
Someone help me rectify it
zsh: parse error near `\n'

Hi, what if my macOS already has python3 and if I installed python3 via brew, its not going to use the brew version. What should I do ? Thanks!

hello all,
I have the same error:

if it fails for you in:
virtualenv -p python3 <desired_path>
Try:
python3 -m virtualenv <desired_path>

If i use both of this i get this error
Someone help me rectify it
zsh: parse error near `\n'

can someone help me please ???

Creation of virtualenv:
python3 -m venv <desired_path>

To create a virtual environment, go to your project’s directory and run venv. If you are using Python 2, replace venv with virtualenv in the below commands.

Got below error after enter: pip3 install virtualenv, how do I resolve this?

Defaulting to user installation because normal site-packages is not writeable
Requirement already satisfied: virtualenv in /Users/fanyang/Library/Python/3.8/lib/python/site-packages (20.15.1)
Requirement already satisfied: distlib<1,>=0.3.1 in /Users/fanyang/Library/Python/3.8/lib/python/site-packages (from virtualenv) (0.3.4)
Requirement already satisfied: six<2,>=1.9.0 in /Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.8/lib/python3.8/site-packages (from virtualenv) (1.15.0)
Requirement already satisfied: platformdirs<3,>=2 in /Users/fanyang/Library/Python/3.8/lib/python/site-packages (from virtualenv) (2.5.2)
Requirement already satisfied: filelock<4,>=3.2 in /Users/fanyang/Library/Python/3.8/lib/python/site-packages (from virtualenv) (3.7.1)

if it fails for you in: virtualenv -p python3 <desired_path> Try: python3 -m virtualenv <desired_path>

Thanks so much! Only this command gets worked for my Mac!