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virtualenv: command not found in Python

I am trying to create a new virtual environment for a tutorial. I have installed virtualenv and virtualenvwrapper multiple times but every time I try creating a new virtual environment my terminal displays - mkvirtualenv: command not found. When I try finding out the version of virtualenv it shows virtualenv: command not found. Something similar was happening with my pip installation as well but then it got resolved when I used some command.
I would like to point out that my PATH seems to be really messed up. The PATH is pointing to /Library/Frameworks/Python.framework/Versions/3.8/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/Library/Apple/usr/bin. Please help.
I saw something else when I use pip show virtualenv it gives me details of the version and the author but when I use virtualenv --version it sends a virtualenv: command not found.

First of all, you will need to install virtualenv as it is a python 2 external dependency.
pip install virtualenv
this will allow you to use virtualenv globally.
Alternatively, you can use from Python 3.5+
python -m virtualenv venv
However if you dont wish to support python 2 you can use venv which is installed on from python 3.3
python3 -v venv venv

Took quite some time to figure it out but what worked for me was to install it using pip3 install instead of pip install
pip3 install virtualenv

Your PYTHONPATH points to a site-packages dir for Python 3.x but you are running Python 2.x

I'm running on macOS 10.12, and I'm trying to install Django using:
pip install Django==1.10.5
I get this error:
Your PYTHONPATH points to a site-packages dir for Python 3.x but you are running Python 2.x!
PYTHONPATH is currently: "/usr/local/lib/python3.6/site-packages:"
You should `unset PYTHONPATH` to fix this.
I have Python3 and Python2.7 installed with macOS on my system, but I really only want to use Python3 for pretty much everything. Pretty new to using / configuring Python, has anyone else come across this?

You shouldn't have site-packages in your PYTHONPATH at all; it's already going to be in sys.path for the appropriate version of Python, but having it in PYTHONPATH mean the other version of Python will try to use the incompatible modules found there. Figure out where you are setting PYTHONPATH to that (it shouldn't happen in any default setup, so you probably did the wrong thing in ~/.bashrc or the like manually), and stop doing it. If you can't figure it out, unset PYTHONPATH will remove it.
Since you want to use Python 3, use pip3 for package management, not pip.

You'll definitely want to use a virtualenv to separate your Django project from the system Python version. virtualenv creates a virtual environment - a dedicated version of Python just for your Django project - so you don't install any libraries with the system Python version, which is used for many other things. virtualenvwrapper makes working with virtualenv easy. pip install virtualenvwrapper is your friend. Here's how to install:
# Install virtualenvwrapper with the system Python version
pip install virtualenvwrapper
# Then, add these lines to your .bashrc, with the appropriate path to Python 3
# You can find the path to Python 3 with "which python3"
# virtualenvwrapper.sh is typically in /usr/bin or /usr/local/bin
export VIRTUALENV_PYTHON=/usr/local/bin/python3.5
source /usr/bin/virtualenvwrapper.sh
After that initial install, here's how to work with virtualenvwrapper:
# Make a virtualenv
mkvirtualenv my_project
# You're now in the environment for your project
pip install Django
# When you need to activate the virtualenv to work on your project
workon my_project
# Show the virtualenvs you've created - I use one for each Django or Python project I create
lsvirtualenv
Much more here: https://virtualenvwrapper.readthedocs.io/en/latest/
Good luck!

virtualenv does not include pip

I am trying to create a virtual environment using virtualenv on Mac OS X El Capitan. I have installed Python 2.7.11 with brew, which includes pip, wheel and setuptools by default.
Hovewer, when I try to install virtualenv following instructions in the documentation or from any other resource, I get several problems:
virtualenv executable is not placed in /usr/local/bin after pip makes its job, so I need to ln -s it by hand (it may indicate, that there is something wrong with installation on this step).
After I run virtualenv venv, it creates new environment, catches Python 2.7.11 from brew-installation, but: there is no pip inside bin folder. That means, that if I try which pip, having venv activated, it returns a global position of pip — /usr/local/bin/pip, not /path/to/venv/bin/pip.
As a consequence, installing packages inside venv uses global pip and installs them to a global sites-packages, not that inside venv, and it's quite the opposite of what environment should do.
Could you please suggest what may be wrong and how to fix it?
EDIT: The thing to mention is that I used to have other versions of Python installed on my computer, which I have recently deleted as it is described in this answer. Maybe it causes the issue, and some more thorough cleaning is needed.

Try removing or renaming the .pydistutils.cfg file in your home directory, e.g. by renaming with mv ~/.pydistutils.cfg ~/oldpydistutils.cfg
I'm putting a detailed answer here to help others, but the original credit goes to this answer. If you know what specifically in .pydistutils.cfg was causing the problem, let me know!
I was having the same issue: my virtual environments were created without a local copy of pip, although they had a local copy of python. This meant that using $ pip from within the virtual environment installed to the global package location, and was not visible to the environment's python.
How I diagnosed this on my machine:
I create a virtualenvironment with $ virtualenv env
Activated the virtual environment with $ source env/bin/activate
Checked python location: run (env)$ which python with output /Users/<username>/env/bin/python (as expected)
Checked pip location: run (env)$ which pip with output /usr/local/bin/pip (NOT expected)
To check where our packages are going, we can try to install a package in the virtual environment:
Try to install a package: (env)$ pip install HTTPServer which succeeds
Try to run the package: (env)$ python -m HTTPServer which fails with error /Users/emunsing/env/bin/python: No module named HTTPServer
To double-check, try to install again: (env)$ pip install HTTPServer which produces Requirement already satisfied (use --upgrade to upgrade): HTTPServer in /usr/local/lib/python2.7/site-packages
Double-checking, we see that there's no Pip in the environment's /bin folder:
$ ls env/bin
activate activate.fish python python2
activate.csh activate_this.py python-config python2.7
And so while the system finds the local python version, it can't find a local pip to use and traverses the $PATH. It ended up using pip from /usr/local/bin, leaving me unable to install packages locally to the virtual environment.
Here's what I tried:
- Reinstalling python brew uninstall python followed by brew upgrade and brew install python --build-from-source
- Installing pip using the get-pip.py command as described in the Pip documentation
Here's what I ruled out:
- I was not using sudo pip ... which caused similar problems in this other question and haven't done so at any time on this Python/pip install
- My virtual environment didn't show a local installation of pip, as was the case in these similar questions: This one for Windows, This one for Mac OS X.
Ultimately, I found that eliminating the ~/.pydistutils.cfg file fixed the problem, allowing for fresh virtual environments that had their own local pip. The contents of my ~/.pydistutils.cfg file were:
[global]
verbose=1
[install]
install-scripts=$HOME/bin
[easy_install]
install-scripts=$HOME/bin
Simply renaming the ~/.pydistutils.cfg file appears to fix the problem: it seems that although this file was created by the homebrew installation, some settings in this file may be incompatible with virtualenv. While removing this file hasn't had any bad effects on my system, you may need to use the --user flag when installing packages with pip to the global environment (e.g. $ pip install --user HTTPServer). Here are more details on .pydistutils.cfg if you want to work on tailoring it for your needs.

virtualenv executable is not placed in /usr/local/bin after pip makes its job, so I need to ln -s it by hand (it may indicate, that there is something wrong with installation on this step).
Don't do that. That will only hide the bug and not solve the problem. Here's a short guide how to debug this kind of issues:
Start with which -a python. The first path you see should be /usr/local/bin/python, if not check your PATH variable.
Next, check which -a pip. Again the first path should be /usr/local/bin/pip. If not, run python -m ensurepip and recheck.
Now install virtualenv using pip install virtualenv, after that check the output of which -a virtualenv. The first path should be /usr/local/bin/virtualenv, if not check the output of env |grep PYTHON for unexpected environment variables.
Finally check the output of virtualenv --version to make sure you have the latest version.

I had the issue when running virtualenv: "ImportError: No module named pip."
My solution was to downgrade virtualenv. I had 16.2.0.
pip uninstall virtualenv
pip install virtualenv==15.1.0

Just hit same issue on Linux. Seems like there are multiple causes of this issue, but for me answer was to remove ~/.pip/.
Details: I had this in my .pip/pip.conf for some reason I can't remember:
$ cat ~/.pip/pip.conf
[global]
use_https = True
index = https://pypi.python.org/pypi
prefix = /home/sam/local/
and was using local versions on Python, Pip installed at ~/local/. For some reason virtualenv installed pip must pick up prefix = /home/sam/local/ setting and pip was being installed there.

Try this: sudo apt install pythonV.v-distutils.
In my case V.v == 3.8.
This worked for me.

Virtualenv is installing with wrong version of Python

I recently have started learning python and have run into an issue.
When I run python on my mac without virtualenv, the version number is Python 2.7.5. Unfortunately, when I go into my virtualenv, and run Python, the version number is Python 2.6.1.
I tried, creating another virtualenv using:
virtualenv -p /usr/bin/python2.7 newdev
but got: The executable /usr/bin/python2.7 (from --python=/usr/bin/python2.7) does not exist

You have to specify the executable, not the whole path. For example:
mkvirtualenv --python=python3 mynewenv

virtualenv --python=python3 mynewenv

How to use Python virtualenv

The scenario is: I am on Ubuntu 11 which comes with Python 2.7, I want to run Mozilla JetPack which supports Python 2.5/2.6 and Google App Engine which only supports Python 2.5.
Read that its not a good idea to remove Python 2.7 as Ubuntu maybe using it. So the correct way is to use virtualenv. But I am quite lost using it. I installed Python 2.5 in /usr/local/python25 following this guide
I tried
jiewmeng#JM:/usr/local/python25/bin$ ./python --version
Python 2.5.5
jiewmeng#JM:/usr/local/python25/bin$ ./python virtualenv /works/tmp/test
./python: can't open file 'virtualenv': [Errno 2] No such file or directory
then the below works but I will be using Python 2.7
jiewmeng#JM:/usr/local/python25/bin$ virtualenv /works/tmp/test
New python executable in /works/tmp/test/bin/python
Installing distribute.................................................................................................................................................................................done.
jiewmeng#JM:/usr/local/python25/bin$ cd /works/tmp/test/bin
jiewmeng#JM:/works/tmp/test/bin$ ls
activate activate_this.py easy_install easy_install-2.7 pip python
jiewmeng#JM:/works/tmp/test/bin$ ./python --version
Python 2.7.1+
Also, how do I then run Mozilla JetPack or Google App Engine with this version of Python? Sorry I am new to Python (and Linux/Ubuntu)

Outline:
First cd to /usr/local/python25/bin
Download setuptools for Python2.5 (setuptools-0.6c11-py2.5.egg)
Install it (sh setuptools-0.6c11-py2.5.egg).
Now install pip (easy_install pip).
Install virtualenv and virtualenvwrapper using pip (pip install v... etc.).
Configure WORKON_HOME for virtualenv wrapper to work (export WORKON_HOME = $HOME/.virtualenvs). You can use any other directory you want (not just $HOME/.virtualenvs). Just make sure to use the full path.
Now create a virtualenv (mkvirtualenv foobar).
Switch to the new virtualenv (workon foobar).
Now install GAE, JetPack and whatever you want using pip install blah
Why did your install not work?
Looks like you did not install virtualenv for Python2.5. Hence this will not work.
jiewmeng#JM:/usr/local/python25/bin$ ./python virtualenv /works/tmp/test
You can check by running ls command in that directory. I suspect you won't find virtualenv file there.
However this worked for you.
jiewmeng#JM:/usr/local/python25/bin$ virtualenv /works/tmp/test
Because it is using the virtualenv file for system default Python2.7. You can check which virtualenv and opening the virtualenv script. You'll see that the #! will point to system default python.
So you need to install the easy_install and pip for Python 2.5 before you can create virtualenv for Python 2.5. Just follow the steps outlined above.

You don't need to do anything fancy outside the virtualenv wrapper. Just use the --python=python2.5 flag (check out the man page for virtualenv form more). It does not matter what version you install it with, you just have to select the right executable for python in the virtual environment.
e.g. mkvirtualenv --python=python2.5 --distribute python25 if the python flag fails, either add a symlink (ln -s) to python25 in your $PATH or use the full path name on the python flag.
Also, default for multiple python installations is to have, for all 'altinstall' versions, a separate python and easy_install. So, for example: python2.5 ,easy_install-2.5 ,python2.6, easy_install-2.6 etc.