Installing Python#
Overview#
Your workflow should also anticipate some of the following challenges:
- You are going to work on multiple projects with varying lifespans and potentially conflicting dependencies.
- The language, some of the Python packages you use, or the packages those packages depend on are going to change while you work.
However, you are responsibile for when changes in the language or your dependencies make their way into your projects. Keeping track of which version of Python you're using is an important first step that will make it easier to share your projects with other people, switch between projects, and debug problems with your code.
How should I install Python?#
Warning
A version of Python may come installed with your operating system. Do not delete or modify it.1 Forget it exists.
How you will manage your Python installations depends on whether you manage your own desktop or are working on a server:
Instructions for installing Python are outlined here.
Each version of Python on the server will be installed at /opt/python/{PYTHON_VERSION}.
Terminal
ubuntu@ip-172-98-23-134:~$ export PYTHON_VERSION="3.8.13"
ubuntu@ip-172-98-23-134:~$ curl -O https://cdn.rstudio.com/python/ubuntu-2004/pkgs/python-${PYTHON_VERSION}_1_amd64.deb
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 57.0M 100 57.0M 0 0 30.9M 0 0:00:01 0:00:01 --:--:-- 30.8M
ubuntu@ip-172-98-23-134:~$ sudo gdebi python-${PYTHON_VERSION}_1_amd64.deb
Reading package lists... Done
Building dependency tree
Reading state information... Done
Reading state information... Done
Requires the installation of the following packages: libev-dev libev4
interactive high-level object-oriented language
Do you want to install the software package? [y/N]:y
...
Preparing to unpack python-3.8.13_1_amd64.deb ...
Unpacking python-3.8.13 (1) ...
Setting up python-3.8.13 (1) ...
ubuntu@ip-172-98-23-134:~$ export PYTHON_VERSION="3.9.13"
ubuntu@ip-172-98-23-134:~$ curl -O https://cdn.rstudio.com/python/ubuntu-2004/pkgs/python-${PYTHON_VERSION}_1_amd64.deb
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 58.9M 100 58.9M 0 0 36.1M 0 0:00:01 0:00:01 --:--:-- 36.1M
ubuntu@ip-172-98-23-134:~$ sudo gdebi python-${PYTHON_VERSION}_1_amd64.deb
Reading package lists... Done
...
Preparing to unpack python-3.9.13_1_amd64.deb ...
Unpacking python-3.9.13 (1) ...
Setting up python-3.9.13 (1) ...
ubuntu@ip-172-98-23-134:~$ ls /opt/python
3.8.13 3.9.13
ubuntu@ip-172-98-23-134:~$ which python
Install pyenv or pyenv for Windows. An easy way to do this is with a package manager2.
Warning
Do not depend a version of Python installed by your package manager.
Your package manager may update Python in a manner incompatible with your data science projects, while other software managed via your package manager may expect the version of Python managed by your package manager to be updated.
Using pyenv will help you decouple managing your data science projects from keeping other software on your system up to date.
Once pyenv is installed, install a version of Python.
Note
To make sure the version of Python you install will work with reticulate, add PYTHON_CONFIGURE_OPTS="--enable-shared" to your pyenv install command, as illustrated below.
You can also add this instruction to your shell profile to ensure that it is always set.
Python installation may also fail due to missing system dependencies.
Terminal
WDAGUtilityAccount@mvp MINGW64 ~/Documents
$ PYTHON_CONFIGURE_OPTS="--enable-shared" pyenv install 3.9.2
:: [Info] :: Mirror: https://www.python.org/ftp/python
:: [Downloading] :: 3.9.2 ...
:: [Downloading] :: From https://www.python.org/ftp/python/3.9.2/python-3.9.2-amd64-webinstall.exe
:: [Downloading] :: To C:\Users\WDAGUtilityAccount\scoop\apps\pyenv\current\pyenv-win\install_cache\python-3.9.2-amd64-webinstall.exe
:: [Installing] :: 3.9.2 ...
:: [Info] :: completed! 3.9.2
$ PYTHON_CONFIGURE_OPTS="--enable-shared" pyenv install 3.7.7
:: [Info] :: Mirror: https://www.python.org/ftp/python
:: [Downloading] :: 3.7.7 ...
:: [Downloading] :: From https://www.python.org/ftp/python/3.7.7/python-3.7.7-amd64-webinstall.exe
:: [Downloading] :: To C:\Users\WDAGUtilityAccount\scoop\apps\pyenv\current\pyenv-win\install_cache\python-3.7.7-amd64-webinstall.exe
:: [Installing] :: 3.7.7 ...
:: [Info] :: completed! 3.7.7
WDAGUtilityAccount@mvp MINGW64 ~/Documents
$ pyenv rehash
Calling python if no global version is set will result in a prompt encouraging you to select one.
Terminal
WDAGUtilityAccount@mvp MINGW64 ~/Documents
$ python --version
No global python version has been set yet. Please set the global version by typing:
pyenv global 3.7.2
WDAGUtilityAccount@mvp MINGW64 ~/Documents
$ pyenv global 3.9.2
WDAGUtilityAccount@mvp MINGW64 ~/Documents
$ python --version
Python 3.9.2
You can also set a Python version for use with specific projects:
Terminal
WDAGUtilityAccount@mvp MINGW64 ~/Documents
$ mkdir older-data-science-project
WDAGUtilityAccount@mvp MINGW64 ~/Documents
$ cd older-data-science-project/
WDAGUtilityAccount@mvp MINGW64 ~/Documents/older-data-science-project
$ python --version
Python 3.9.2
WDAGUtilityAccount@mvp MINGW64 ~/Documents/older-data-science-project
$ pyenv local 3.7.7
WDAGUtilityAccount@mvp MINGW64 ~/Documents/older-data-science-project
$ python --version
Python 3.7.7
WDAGUtilityAccount@mvp MINGW64 ~/Documents/older-data-science-project
$ cd ..
WDAGUtilityAccount@mvp MINGW64 ~/Documents
$ python --version
Python 3.9.2
Once you've installed the versions of Python you need, the next step is to install packages.
-
If you are working in Windows 10, you will want to disable the Python "App execution aliases" as described in this Stack Overflow post. ↩
-
webi, Homebrew, scoop, and chocolatey are package managers. ↩