python, django version selection, python installation under linux, installation of python under windows

Article Table of Contents

• 1. Python version selection
• • Comparison between Django version and Python version
• 2. Python installation under Linux
• • ubuntu20.04 installation
  • • **Linux Ubuntu 20.04 LTS One-click installation of Python3 different versions**
  • centos8 compiles and installs Python 3.8.10
  • • During the compilation process Problems encountered
    • • Prompt that compilation is successful ，Some modules are not compiled properly
      • The _ctypes module is missing
    • Create a virtual environment
• 3. Install python under windows
• • Installing python 3.10 under windows

1. python version selection

Official download address：https://www. python.org/downloads/

First of all, there are the choices of Python2.x and Python3.x. These are two major versions. Currently, version updates and technical support for Python 2.x have been officially stopped. The last version of Python2.x is Python2.7.18 released in 2020.

Python 3.x is not a simple upgrade of Python 2.x. In order not to bring too much burden, Python 3.x was not designed with backward compatibility in mind. Therefore ，If it is not the maintenance of old code，our new code is recommended to use Python3.x.

ok，The next step is Python3.x. How do we choose?

Let’s look at the official python 3.8.14 description first
Note：The version you are viewing Is Python 3.8.13 – It is a security bug fix version of the older 3.8 series. Python 3.10 is now the latest feature release series for Python 3.

For example：According to the release calendar specified in PEP 569，Python 3.8 is now in the “Security Fixes Only” phase of its lifecycle：3.8 The branch only accepts security fixes，and these fixes will be released in source code only form from time to time until October 2024. Python 3.8 no longer receives general bug fixes， and a binary installer is no longer provided for it. Python 3.8.10 is the last complete bug-fix release of Python 3.8，with a binary installer.

You can see that Python 3.8 “officially no longer provides a binary installer” and only fixes security issues in the form of source code.

Let’s look at the official python 3.9.14 again
Note ：The version you are looking at is Python 3.9.14， It is a security bug fix for the old 3.9 series Version.

No installer
According to the release calendar specified in PEP 596，Python 3.9 is now in the “Security Fixes Only” phase of its lifecycle：The 3.9 branch only accepts security fixes ，And will be released in source code only form from time to time until October 2025. Python 3.9 no longer receives regular bug fixes and a binary installer is no longer provided for it. Python 3.9.13 is the last complete bug-fix release of Python 3.9 with a binary installer.

Summary：The latest version is 3.10.x，The previous versions only fix security issues，If there are security issues，We need to download the latest Source code compilation uses fixes.

Overall, it’s not a big problem. If we take into account the stability issues of the latest version and the compatibility issues of some common frameworks and Python versions, we will Use versions 3.8 and 3.10，Use source code to compile！

The default Python version of Ubuntu 20.04 LTS is 3.8.10.
Ubuntu 22.04 LTS (Jammy Jellyfish). However, the default Python 3 version of this version is Python 3.10， which is higher than the 3.9, 3.8 or even earlier versions that many developers are using.

Comparison between Django version and Python version

Official link：https://www.djangoproject.com/download/

Django in BSD Open source under license. We recommend using the latest version of Python 3. The last version to support Python 2.7 was Django 1.11 LTS. For information on which Python versions each version of Django supports, see the FAQ.

Personal work skills：After we have selected python， we just use pip to install django and various dependencies，without the version number，In this way, all dependencies are basically the same as the current python Compatible and matching.

2. Python installation under Linux

ubuntu20.04 installation

The default Python version of Ubuntu 20.04 LTS is 3.8.10.
Ubuntu 22.04 LTS (Jammy Jellyfish). However, the default Python 3 version of this version is Python 3.10, which is higher than the 3.9, 3.8 or even earlier versions that many developers are using.

3.8.10 is still more mainstream，It is recommended to use the default！
3.10 seems to be a good choice too！If you use Ubuntu 22.04 LTS directly，Use Python 3.10 development will be smoother and there is no need to reinstall python.

Linux Ubuntu 20.04 LTS One-click installation of Python3 different versions

Add Python software source， to facilitate us to install.
sudo apt update
sudo apt install software-properties-common
#Add Deadsnakes PPA&#xff08 ;A very easy-to-use third-party software source）：
sudo add-apt-repository ppa:deadsnakes/ppa
sudo apt update
#Install different versions of Python3, such as ：3.10
sudo apt install python3.10


Update the default python pointing to python3.10
First ，delete the original link

rm /usr/bin/python
which python3
ln -s /usr/bin/python3.10 /usr/bin/pythonrm /usr/bin/python3
ln -s /usr /bin/python3.10 /usr/bin/python3


Install pip

sudo apt install python3-pip


When installing venv, you must specify the specific version number consistent with the python environment, such as python3.10

sudo apt install python3.10-venv


Activate virtual environment

source venv/bin/activate


Exit the virtual environment

deactivate


centos8 compilation Install Python 3.8.10

Build Python3.8 running environment on CentOS8
Reference URL: https://www.modb.pro/db/144965
Install Python3.8 on Centos7 Detailed tutorial
Reference URL: https://blog.csdn.net/u010786653/article/details/122690588

1. Follow the dependencies needed to compile python：

sudo yum -y install gcc gcc-c++ zlib-devel bzip2-devel openssl-devel sqlite-devel readline-devel libffi-devel
sudo yum install zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite-devel readline-devel tk-devel xz-devel gdbm-devel


2. Download python to the temporary directory

VERSION=3.8.10
wget -P /tmp/ https://www.python.org /ftp/python/${VERSION}/Python-${VERSION}.tgz


Download to the temporary directory and compile，

tar -xvzf /tmp/Python-${VERSION}.tgz -C /tmp/
cd /tmp/Python-${VERSION}


3. Compile

Specify the installation directory as $HOME/python3（This step will take a long time）

mkdir -p $HOME/python3
#./configure -- prefix=/usr/local/python3
./configure --prefix= $HOME/python3 --enable-optimizations


The –enable-optimizations option is run multiple times by Test， to optimize Python binaries. This will make the build process slower.

nproc
make -j 8


Modified to correspond to the number of cores in the processor. You can find your processor core count by running nproc.
PS: The nproc command can display the number of CPUs available to the current process，This number may be less than the actual number of jobs

After the generation process is completed，Install the Python binaries（ Please do not use the standard make install as it will overwrite the default system Python binaries.

sudo make altinstall


The difference between make altinstall and make install， altinstall skips creating the python link and the manual pages links.
altinstall skips creating python links and man page links.
If you use make install，there will be two different versions of Python in the /usr/bin/ directory on the system，This will cause many problems.
Therefore, we can solve this problem by configuring the compilation and installation path in configure.

Summary：If our compilation parameters do not configure the installation path，If we use the default installation path，, we need to use make altinstall. So generally when there are multiple versions, we can just use make altinstall directly. #xff0c; Still some modules have not been compiled

Python build finished successfully! #Prompt for successful installation
The necessary bits to build these optional modules were not found:
_dbm _gdbm _lzma
/> _tkinter nis

yum install zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite -devel readline-devel tk-devel xz-devel gdbm-devel


Missing _ctypes module

There is a built-in module in python3 called ctypes& #xff0c; It is an external function library module of python3，Provides data types compatible with C language，and calls the shared library under Linux system through it，This module requires centos7 The development link library (header file and link library) of the foreign function library (Foreign function library) in the system – and the development link library software package of the external function library (libffi) is not installed in the centos7 system.

Install the libffi package

yum install libffi-devel

Create a virtual environment

The Python virtual environment is a self-contained directory tree& #xff0c;It contains Python installation and a lot of other packages. It allows you to install Python modules in an isolated location for a specific project rather than installing them globally. This way you don’t have to worry about affecting other Python projects.

In this example ，we will create a new Python 3.8 project，called in the user’s home directory. my_app

First，create the project directory and switch to：

mkdir ~/my_app && cd ~/my_app


Run the following command from inside the project root to create a file named ：my_app_venv

python3.8 -m venv my_app_venv


Activate environment：

source my_app_venv/bin/activate


After activation, the shell prompt will be prefixed with the environment name. Starting with Python 3.4 – when creating a virtual environment – Python’s package manager pip will be installed by default.

3. Install python under windows

Install python 3.10 under windows

1. Official website download：https://www.python.org/ downloads/release/python-3108/
2. Installation
   

�Number of cores. You can find your processor core count by running nproc.
PS: The nproc command can display the number of CPUs available to the current process，This number may be less than the actual number of jobs

After the generation process is completed，Install the Python binaries（ Please do not use the standard make install as it will overwrite the default system Python binaries.

sudo make altinstall


The difference between make altinstall and make install， altinstall skips creating the python link and the manual pages links.
altinstall skips creating python links and man page links.
If you use make install，there will be two different versions of Python in the /usr/bin/ directory on the system，This will cause many problems.
Therefore, we can solve this problem by configuring the compilation and installation path in configure.

Summary：If our compilation parameters do not configure the installation path，If we use the default installation path，, we need to use make altinstall. So generally when there are multiple versions, we can just use make altinstall directly. #xff0c; Still some modules have not been compiled

Python build finished successfully! #Prompt for successful installation
The necessary bits to build these optional modules were not found:
_dbm _gdbm _lzma
/> _tkinter nis

yum install zlib-devel bzip2-devel openssl-devel ncurses-devel sqlite -devel readline-devel tk-devel xz-devel gdbm-devel


Missing _ctypes module

There is a built-in module in python3 called ctypes& #xff0c; It is an external function library module of python3，Provides data types compatible with C language，and calls the shared library under Linux system through it，This module requires centos7 The development link library (header file and link library) of the foreign function library (Foreign function library) in the system – and the development link library software package of the external function library (libffi) is not installed in the centos7 system.

Install the libffi package

yum install libffi-devel

Create a virtual environment

The Python virtual environment is a self-contained directory tree& #xff0c;It contains Python installation and a lot of other packages. It allows you to install Python modules in an isolated location for a specific project rather than installing them globally. This way you don’t have to worry about affecting other Python projects.

In this example ，we will create a new Python 3.8 project，called in the user’s home directory. my_app

First，create the project directory and switch to：

mkdir ~/my_app && cd ~/my_app


Run the following command from inside the project root to create a file named ：my_app_venv

python3.8 -m venv my_app_venv


Activate environment：

source my_app_venv/bin/activate


After activation, the shell prompt will be prefixed with the environment name. Starting with Python 3.4 – when creating a virtual environment – Python’s package manager pip will be installed by default.

3. Install python under windows

Install python 3.10 under windows

1. Official website download：https://www.python.org/ downloads/release/python-3108/
2. Installation