Install Python 3.4 on Raspberry Pi
The resulting setup will use virtualenv + convenience wrapper and install Python 3.4 under /opt to prevent any (future) collisions with the system Python.
Disclaimer
- Apparently all the you are supposed to use
pyenvnow, but that’s too much new stuff at once for me. - My Linux fu is pretty weak, so this was a lot of try and error. Please leave a comment, if you have any improvements.
Preparation
Create a backup of your SD card!
sudo apt-get install rpi-update
sudo rpi-update # update the firmware
sudo reboot # reboot needed
sudo apt-get update # update package information
sudo apt-get dist-upgrade # upgrade everything, resolving dependencies
# now we should be up to date - yay
# update pip
sudo pip install -IU pip
# virtualenv and a handy wrapper
sudo pip install -IU virtualenv virtualenvwrapper
During my fist attempt I later ran into the following error while installing pip:
Installing setuptools, pip...
Complete output from command /home/pi/.virtualenvs/python34/bin/python3.4 -c "import sys, pip; sys...d\"] + sys.argv[1:]))" setuptools pip:
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "/usr/local/lib/python2.7/dist-packages/virtualenv_support/pip-1.5.6-py2.py3-none-any.whl/pip/__init__.py", line 10, in <module>
File "/usr/local/lib/python2.7/dist-packages/virtualenv_support/pip-1.5.6-py2.py3-none-any.whl/pip/util.py", line 18, in <module>
File "/usr/local/lib/python2.7/dist-packages/virtualenv_support/pip-1.5.6-py2.py3-none-any.whl/pip/_vendor/distlib/version.py", line 14, in <module>
File "/usr/local/lib/python2.7/dist-packages/virtualenv_support/pip-1.5.6-py2.py3-none-any.whl/pip/_vendor/distlib/compat.py", line 66, in <module>
ImportError: cannot import name 'HTTPSHandler'
----------------------------------------
...Installing setuptools, pip...done.
Traceback (most recent call last):
File "/usr/local/lib/python2.7/dist-packages/virtualenv.py", line 2338, in <module>
main()
File "/usr/local/lib/python2.7/dist-packages/virtualenv.py", line 824, in main
symlink=options.symlink)
File "/usr/local/lib/python2.7/dist-packages/virtualenv.py", line 992, in create_environment
install_wheel(to_install, py_executable, search_dirs)
File "/usr/local/lib/python2.7/dist-packages/virtualenv.py", line 960, in install_wheel
'PIP_NO_INDEX': '1'
File "/usr/local/lib/python2.7/dist-packages/virtualenv.py", line 902, in call_subprocess
% (cmd_desc, proc.returncode))
OSError: Command /home/pi/.virtualenvs/python34/bin/python3.4 -c "import sys, pip; sys...d\"] + sys.argv[1:]))" setuptools pip failed with error code 1
Aparently SSL is needed as dependency and needs to be install before compiling python, so I did this whole thing twice. Luckily I don’t have anything else to do…
To make sure I don’t have to do this a third time, I started digging around, trying to find a complete list of dependencies. First, I installed apt-rdepends sudo apt-get install apt-rdepends and ran it:
pi@whatever ~ $ apt-rdepends python3.2 | grep ^lib
Reading package lists... Done
Building dependency tree
Reading state information... Done
libbz2-1.0
libc6
libc-bin
libgcc1
libdb5.1
libffi5
libncursesw5
libtinfo5
libreadline6
liblzma5
libselinux1
libsqlite3-0
libssl1.0.0
libexpat1
Unfortunately Python 3.4 is not in the index yet, which is the reason why we’re compiling from source in the first place. I was just hoping the dependencies didn’t change too much since Python 3.2.
To see what already is installed, you can search for packages with dpkg --get-selections | grep -v deinstall | grep ^libbz.
I just installed the whole buch plus the corresponding dev packages.
sudo apt-get install libbz2-1.0 libbz2-dev libffi5 libffi-dev libncursesw5 libncursesw5-dev libreadline6 libreadline6-dev liblzma5 liblzma-dev libsqlite3-0 libsqlite3-dev libexpat1 libexpat1-dev libssl-dev openssl
Installation
Head over to https://www.python.org/downloads/ and copy the link to the gzipped source tarball of the Python version you want to install. 3.4.1 was the latest version as of writing this.
# get the source
cd /tmp
wget https://www.python.org/ftp/python/3.4.1/Python-3.4.1.tgz
tar xvzf Python-3.4.1.tgz
cd Python-3.4.1/
# configure, make, make install
./configure --prefix=/opt/python3.4 # this takes a little bit (~ 5 minutes)
make # this takes aaages (about an hour)
sudo make install # this is rather quick again (~ 7 minutes)
Add source /usr/local/bin/virtualenvwrapper_lazy.sh to your ~/.bashrc.
I rebooted at this point. Don’t know if it’s really necessary.
Finally, create a virtual python environment with mkvirtualenv python34 -p /opt/python3.4/bin/python3.4. Fingers crossed, no errors and you get:
(python34)pi@whatever /tmp/Python-3.4.1 $ python --version
Python 3.4.1
To find out how to work with python virtual environments, check out the virtualenvwrapper command documentation.