I have installed python-django in a ubuntu 14.04, unfortunately I need to use exactly that distribution, but it is unsupported now, to update django I used the pip, how do I use the newer version instead of the apt version?
You need virtualenv. It enables you to create a virtual python environment with its own packages (instead of system-wide packages).
First, install python-virtualenv package with apt-get:
$ sudo apt-get install python-virtualenv # or python3-virtualenv if you use python 3
And create a virtualenv:
$ virtualenv /home/user/venv
Then activate the virtualenv you created (after doing this, you will be using only the packages you installed in this virtualenv, ignoring the system-wide packages):
$ source /home/user/venv/bin/activate
Now you can install the packages you want:
$ pip install django==1.7 # replace 1.7 with the version you need
or if you want to install the latest version currently available (be careful here, in future you can install latest version and the version can be different from the version you worked on)
$ pip install django
After this point, whenever you run python manage.py runserver in a django project, you will be using the django package you installed in this virtualenv.
Extra notes:
You can save the packages you installed, in order to be able to install them again on another virtualenv:
$ pip freeze > requirements.txt
And then you can install the list of packages you saved later with:
$ pip install -r requirements.txt
Related
I was creating a new virtual environment on Ubuntu 20.04:
$ virtualenv my_env
But it gave an error:
ModuleNotFoundError: No module named 'virtualenv.seed.embed.via_app_data'
Other info:
$ virtualenv --version
virtualenv 20.0.17 from /usr/lib/python3/dist-packages/virtualenv/__init__.py
#yushulx
I also ran into the same issue. I installed both via pip3 and via sudo apt install python3-virtualenv and it gave me an error but after I ran pip3 uninstall virtualenv I could create a virtualenv without issue
Try to create the virtual environment using directly venv module
python3 -m venv my_env
To fix this on Ubuntu 20.04, I had to uninstall virtualenv from the system: apt remove python3-virtualenv, and reinstall it using pip: pip install --user virtualenv --force-reinstall. I had errors about dependencies conflicts, I fixed them by calling pip install --user ${package} --force-reinstall for every package involved.
virtualenv is installed by default with python itself and when you install virtualenv via pip3 and try to create virtual environment using pipenv you will get this error:
ModuleNotFoundError: No module named 'virtualenv.seed.embed.via_app_data
check the version of installed virtualenv using apt list --installed
mine is:
python3-virtualenv/focal,focal,now 20.0.17-1 all [installed,automatic]
with the installed virtualenv by pip3
min is :
virtualenv 20.4.0
default installation of virtualenv is different with pip3 installed virtualenv
so when you try to create a virtual environment using pipenv for example installing django in a directory home/user/djano with pipenv install django~=3.1.5 you will get that error
the solution is remove installed virtualenv using pip3 uninstall virtualenv and use the default installation of virtualenv this time when you create virtual environment with pipenv it will create it successfully.
I want to have virtualenvwrapper. On Debian 10 testing I did:
apt remove python3-virtualenvwrapper # not purge, I want no changes in ~/.virtualenvs/
apt purge python3-virtualenv
/usr/bin/python3.8 -m pip install --force-reinstall virtualenvwrapper
/usr/bin/python3.8 -m pip install --force-reinstall virtualenv==20.0.23
.24 no longer works. I hope it will be solved sometimes...
EDIT 2021.01: I have changed my stack to: pyenv + pyenv-virtualenvwrapper + poetry. Ie. I use no apt or pip installation of virtualenv or virtualenvwrapper, and instead I install pyenv's plugin pyenv-virtualenvwrapper. This is easier way.
If someone encounters this problem inside existing env (when for example using pyenv) you can also use command below (found on GitHub when tried to fix poetry virtual env installation):
pip install --force-reinstall virtualenv
When I installed virtualenv via pip3, it failed to run virtualenv command. Then I changed the installation via:
sudo apt install python3-virtualenv
The virtualenv command can normally work.
I too had this issue. What I found is it is a permissions issue. For some unknown reason ownership of my home directory was off. I did a chown -R for the directory I was using for my project making myself the owner of my own directory and now everything works as normal.
I also had same issue, seems installed version has different user level so I followed their doc and below one work for me:
python3 -m virtualenv --help
To create new environment:
python3 -m virtualenv my_env
I also faced the same issue but after removing virtualenv which was installed with pip3, I could get rid of this error. Uninstall virtualenv with below command (don't forget to use sudo)
sudo pip3 uninstall virtualenv
After this, virtualenv command works totally fine.
It means that there are two virtualenv in your system.
One is "pip install" by sudo or root, the other may be installed by apt(if you are using ubuntu os)
Just uninstall one of them and the error should be fixed.
I fixed this error by removing all virtualenv and virtualenvwrapper related packages on system and reinstall the virtualenv and virtualenvwrapper with pip with below command(as i use ubuntu, so below only show apt)
remove all packages shown in below result
apt list --installed | grep virtualenvwrapper
apt list --installed | grep virtualenvwrapper
install virtualenv virtualenvwrapper with pip
pip install virtualenvwrapper virtualenvwrapper
set ~/.zshrc
export WORKON_HOME=$HOME/.virtualenvs
export PROJECT_HOME=$HOME/amd
export VIRTUALENVWRAPPER_SCRIPT=/home/robot/.local/bin/virtualenvwrapper.sh
export VIRTUALENVWRAPPER_PYTHON=$(which python3)
source /home/robot/.local/bin/virtualenvwrapper.sh
When we use pip3 or python3 to install virtualenv then I got that error too. I had to run each time to create virtualenv (my_env is virtual environment name)
python3 -m virtualenv my_env
But if I install it using
sudo apt install virtualenv
Then virtualenv command works fine.
virtualenv my_env
I got a message in my terminal while install a software : You are using pip version 8.1.1, however version 10.0.0 is available. You should consider upgrading via the 'pip install --upgrade pip' command.
So I upgraded pip version: $ pip install --upgrade pip
Now I am getting this error:
~$ pip install ipython
Traceback (most recent call last):
File "/usr/bin/pip", line 9, in <module>
from pip import main
ImportError: cannot import name main
TL;DR
The 'ideal' solution (Ubuntu/Debian way):
$ python -m pip uninstall pip to uninstall the new pip 10 and retain your Ubuntu/Debian-provided patched pip 8. For a system-wide installation of modules use apt wherever possible (unless you are in a virtualenv), more on it below. In older Ubuntu/Debian versions, always add --user flag when using pip outside of virtualenvs (installs into ~/.local/, default in python-pip and python3-pip since 2016).
If you still want to use the new pip 10 exclusively, there are 3 quick workarounds:
simply re-open a new bash session (a new terminal tab, or type bash) - and pip 10 becomes available (see pip -V). debian's pip 8 remains installed but is broken; or
$ hash -d pip && pip -V to refresh pip pathname in the $PATH. debian's pip 8 remains installed but is broken; or
$ sudo apt remove python-pip && hash -d pip (for Python 3 it's python3-pip) -- to uninstall debian's pip 8 completely, in favor of your new pip 10.
Note: You will always need to add --user flag to non-debian-provided pip 10, unless you are in a virtualenv! Your use of pip 10 system-wide, outside of virtualenv, is not really supported by Ubuntu/Debian. Never sudo pip!
Details:
https://github.com/pypa/pip/issues/5221#issuecomment-382069604
https://github.com/pypa/pip/issues/5240#issuecomment-381673100
Ubuntu 16.04 with Python 2.7.12
Introduction:
Ironically, despite being suggested by pip itself to do such an upgrade via the pip install --upgrade pip command explicitely in the terminal (ugh!), upgrading it is not recommended in prepackaged GNU/Linux distributions. Ubuntu generally expects using APT package manager for any system-wide Python module updates/installs (including of pip itself), for example:
$ sudo apt-get update (resync Ubuntu package index files from sources)
$ apt-cache search <python-package-name> (full text-search on all available packages)
$ apt-cache show <python-package-name> (displays the package description)
$ sudo apt-get install python-numpy python-scipy python-matplotlib (easily installs heavy modules for data science, resolving all system dependencies automatically)
$ sudo apt-get install ipython (installs the IPython-notebook you were looking for)
$ sudo apt-get install python-pip (installs/upgrades pip to the latest version available in Ubuntu repository – usually slightly behind pypi.org, but it doesn't matter)
If you ever have to use pip install command on Ubuntu/Debian instead of apt-get install, please make sure it runs isolated and does not change the default system-wide Python packages (never use sudo with pip) – more on this below.
ImportError: cannot import name main
The error is caused by the pip install --upgrade pip command: that installs the latest pip version 10 alongside Ubuntu's default pip version from python-pip debian package from the OS distribution (the system Python installation), completely bypassing Ubuntu apt subsystem. It breaks the Ubuntu's default pip: the debian-patched launcher script from python-pip (system-installed to /usr/bin/pip*) tries to do import main() from your newly installed pip 10 library, but with a different import path, so it fails.
This error is discussed in more detail in a developer thread of the pip issue tracker, including a few proposed solutions, such as:
The $ hash -d pip command: when hash is invoked, the full pathname of pip is determined by searching the directories in $PATH and remembered. Any previously-remembered pathname is discarded. The -d option causes the shell to "forget" the remembered location of the given package name; or
Similarly, you can simply re-open a new bash session (a new terminal tab) to refresh pip pathname in $PATH; or
You could just use pip2 command (or pip3 for Python 3) instead of pip to invoke the older system-installed pip script /usr/bin/pip2 , whereas any pip launcher script located in $HOME/.local/bin dir (pip, pip2, pip2.7) will start your new user-installed pip 10 version;
You can also use the versioned Python commands in combination with the -m switch to run the appropriate copy of pip, for example:
$ python2 -m pip install --user SomePackage # default Python 2
$ python2.7 -m pip install --user SomePackage # specifically Python 2.7
That is handy if you have several versions of Python and need an extension from PyPI for a specific Python version. The --user switch is only required when pip is used outside of virtualenv.
Or, uninstall one of the two pips – either user-installed or system-installed – to resolve the conflict:
$ python -m pip uninstall pip – to remove your manually-installed pip in favour of the previously installed Ubuntu-shipped version from python-pip debian package (python3-pip for Python 3); it is slightly older, but it finds and installs latest modules from PyPI just fine, and has a working pip command in the $PATH by default; or
$ sudo apt-get remove python-pip – to uninstall Ubuntu-provided pip in favour of your latest pip 10; if it is not accessible via the short pip command, just add your $HOME/.local/bin directory to your $PATH environment variable to use pip command (see above).
Note: Ubuntu 16.04 pip v8.1.1 and the latest pip v10.0.1 produce exactly the same PyPI index search results and can pull the same module versions;
Finally, you could ignore both pips altogether in favor of APT, and install Python packages system-wide from Ubuntu repo with:
$ apt search <python-package> # e.g. python-pandas
$ apt show <python-package> # e.g. python-flask
$ sudo apt install <python-package>
Packages prefixed with python- are for Python 2; with python3- are for Python 3.
Installation via apt-get may be what you need, in fact, python-packages from Ubuntu repository are preferred whenever possible, particularly in case of heavy system dependencies or when used system-wide. Of course, the amount of Python packages in Ubuntu repository (few thousand!) is relatively smaller compared to PyPI (and have only one version of them), because any OS repository is lagging slightly behind PyPI versions. But the upside of APT is that all the Ubuntu-provided packages underwent integration testing within Ubuntu, plus apt-get quickly resolves heavy dependencies like C extensions automatically. You will always get any required system libraries as part of the apt install, but with pip you have no such guarantees.
APT may not be an option, however, if you really need the latest (or certain older) package version, or when it can only be found at PyPI, or when modules need to be isolated; then pip is indeed more appropriate tool. If you use pip install command on Ubuntu instead of apt-get install, please ensure that it runs in an isolated virtual development environment, such as with virtualenv (sudo apt-get install python-virtualenv), or a built-in venv module (available in python3 only), or at a per-user level (pip install --user command option), but not system-wide (never sudo pip!).
Note: Using sudo pip command (with root access) should be avoided, because it interferes with the operation of the system package manager (apt) and may affect Ubuntu OS components when a system-used python module is unexpectedly upgraded, particularly by dependencies on another pip package. It is advised to never use Pip to change your system-wide Python packages, as these are managed by apt-get on Ubuntu.
I implemmented #catalinpopescu response from ImportError: cannot import name main when running pip --version command in windows7 32 bit
Find pip's path:
$ which pip
Modify file (choose your favorite editor):
$ sudo nano `which pip`
Then modify lines #catalinpopescu said:
Comment/replace lines:
from pip import main
sys.exit(main())
to:
from pip import __main__
sys.exit(__main__._main())
Immediately I upgrade to Pip Version 10.0.1, which appears it hasn't have this error.
try to upgrade the system pip
sudo pip install --upgrade pip
pip install --upgrade pip
this may be useful
I've read a lot of blog post about this and I'm still confused as to what is "best" way to set it up. Most of the blog posts I've read are out-dated. I'm new to Linux and have messed up my system twice now and still can't setup the virtual environments properly. According to what I've read, Virtualenv and Virtualenvwrapper combination is the most widely used setup. So, After a fresh Ubuntu 16.04 LTS install, I do the following:
Install Python 3.6 as shown in the following link.
https://tecadmin.net/install-python-3-6-ubuntu-linuxmint/
The current state of the system now is,
$ python3.6 -V
Python 3.6.4
$ pip3.6 -V
pip 9.0.1 from /usr/local/lib/python3.6/site-packages (python 3.6)
pip3 (python3.5) and pip(python2.7) do not come pre-installed. To install them , I do:
$ sudo apt-get install python-pip
$ sudo apt-get install python3-pip
$ which pip
/usr/bin/pip
$ which pip3
/usr/bin/pip3
Now, the pip-version installed through apt-get method is old(version 8.1.1). We need to update it to (version 9.0.1). This is where it all goes wrong.
Question 1: How do I update the two different pip versions without breaking anything?
Assume, both pip versions are upgraded to version 9.0.1
Now, I have to install virtualenv and virtualenvwrapper.
Which pip version do I use to install it?
$ pip install --user virtualenv and $ pip install --user virtualenvwrapper
or
$ pip3 install --user virtualenv and $ pip3 install --user virtualenvwrapper
ps: I'm following this link-
http://chrisstrelioff.ws/sandbox/2016/09/21/python_setup_on_ubuntu_16_04.html
With python 3.6 virtual environments come built-in with the venv module:
python3.6 -m venv my-venv
To create a virtual environment for python 3.5:
virtualenv -p python3.5 env
To create a virtual environment for python 2.7:
virtualenv -p python2.7 env
Try using conda to set up virtual environments ?
With conda you can create a virtual environment and keep each of them separate from the root environment.
I have a virtualenv (python2api) made in python2.7 on Ubuntu 16.04. In the virtualenv I installed python3.5:
$ virtualenv -p python3.5 python2api
Then I installed pip3:
$ sudo apt-get install python3-pip
But when I run 'which pip' it shows that pip3 installed outside of the virtualenv and any pip3 packages I install go to '/usr/lib/python2.7' instead of '/var/env/python2api/lib/python3.5/site-packages/'.
(python2api) user#comp:/var/env/python2api/lib$ which pip
/var/env/python2api/bin/pip
(python2api) user#comp:/var/env/python2api/lib$ which pip3
/usr/bin/pip3
Is there a way to make pip3 install packages in the virtualenv? It seems like only python2 or only python3 packages can exist in the virtualenv.
A virtualenv encapsulates one version of Python.
You can't use it to manage more than one version, and Python 2.x and Python 3.x are separate versions here.
Use two separate virtualenvs, one for each Python version.
I have a CentOS 6.4 which the default python version is 2.6.
I want to run a virtualenv at python 2.7, so first I try to install python 2.7.
yum install python27
Then I run
virtualenv -p /usr/bin/python2.7 ./venv
Then the output shows that it try to get setuptools from pypi, but my environment can not reach pypi.python.org. I have update the ~/.pip/pip.conf to use a available local source but the virtualenv still get pip from the pypi.python.org. This is one of the things I get confused.
I check the /usr/lib/python2.7/, the site-packages is empty while /usr/lib/python2.6/ is not. So When I use python 2.7, it has nothing available. When I use the default python, it has pip tools installed, it does not need to get it from pypi.python.org.
How can I install pip for python 2.7 individually?
Previous I install pip by
yum install python-setuptools
yum install python-pip
The second question, how to install pip for python2.7 individually can be solved as the following:
Download python source code of the specific version and install it at /usr/local
wget http://python.org/ftp/python/2.7.6/Python-2.7.6.tar.xz
tar xf Python-2.7.6.tar.xz
cd Python-2.7.6
./configure --prefix=/usr/local --enable-unicode=ucs4 --enable-shared LDFLAGS="-Wl,-rpath /usr/local/lib"
make && make altinstall
Then install setuptools and pip
Install easy_install (prepare ez_setup.py beforehand)
python2.7 ez_setup.py
Install pip
easy_install-2.7 pip
easy_intall-2.7 pip need to visit the internet, in my environment I get the pip source file and use "python2.7 setup.py install".
pip2.7 install [packagename]
In my environment I update .pip/pip.conf to use an internal pip source.
(code above take python 2.7 as an example)
To see the details you can check the following url:
http://toomuchdata.com/2014/02/16/how-to-install-python-on-centos/
The first question, when creating a new virtual environment, virtualenv will install setuptools for this environment. If python version is not assigned, it use the system default python and default pip. If pip is not find, then try to get it from pypi.python.org.
In my environment, after python2.7 and pip2.7 installed, when trying to create a new virtualenv, it still get pip from pypi.python.org, I guess that virtualenv does not find the relation between python2.7 and pip2.7.
If you can visit pypi.python.org, that is fine.
If you are at an internal environment that can not visit pypi.python.org, virtualenv provides -extra-search-dir and --never-download command. So you can prepare the setuptools beforehand, copy it from U-disk，using scp, or other solutions.
Move setuptools-0.6c11-py2.7.egg to /usr/local/bin.
Finally we can use virtualenv by
virtualenv -p /usr/local/bin/python2.7 --extra-search-dir /usr/local/bin/ --never-download venv