How to install python3.8/3.7 on ubuntu 21.04

Question

I failed again and again installing python3.8 on my ubuntu 21.04

Now it is 'ok' but this error message appears from pip (and import ctypes doesn't work too):

    Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/local/lib/python3.8/site-packages/setuptools/__init__.py", line 20, in <module>
    from setuptools.dist import Distribution, Feature
  File "/usr/local/lib/python3.8/site-packages/setuptools/dist.py", line 35, in <module>
    from setuptools import windows_support
  File "/usr/local/lib/python3.8/site-packages/setuptools/windows_support.py", line 2, in <module>
    import ctypes
  File "/usr/local/lib/python3.8/ctypes/__init__.py", line 7, in <module>
    from _ctypes import Union, Structure, Array
  File "/usr/local/lib/python3.8/_ctypes/__init__.py", line 8, in <module>
    from _ctypes import Union, Structure, Array
ImportError: cannot import name 'Union' from partially initialized module '_ctypes' (most likely due to a circular import) (/usr/local/lib/python3.8/_ctypes/__init__.py)

Answer 1

You could use the project Conda. Conda is for Python environments. Luckily you can choose the Python version you want to use. Check out at conda.io! Once you're in a Python environment, install any package by conda install PACKAGE. Official documentation: https://docs.conda.io/projects/conda/en/latest/user-guide/concepts/packages.html

To create an environment, use conda create To create a Python 3.8 environment, use the python-variable, an example: conda create -n "name" python=3.8 #quotes not required Then: conda use "name" #quotes not required

Answer 2

Here are to ways to install it, here is how it's done:

=================1=================

first update everything and install following packages

$ sudo apt update
$ sudo apt upgrade
$ sudo apt dist-upgrade
$ sudo apt install build-essential zlib1g-dev libncurses5-dev libgdbm-dev libnss3-dev libssl-dev libreadline-dev libffi-dev wget

Next step is do make a temporary directory and download the source code of python

$ mkdir ~/tmp
$ cd ~/tmp
$ wget https://www.python.org/ftp/python/3.8.1/Python-3.8.1.tgz

next is to extract it and configure it

$ tar -xvzf Python-3.8.1.tgz
$ cd Python-3.8.1
$ ./configure

now install it with

sudo make altinstall

make sure to have sudo privileges while installing everything

=================2=================

Installing it with a third party PPA repo

$ sudo apt update
$ sudo apt install software-properties-common

$ sudo add-apt-repository ppa:deadsnakes/ppa

$ sudo apt update
$ sudo apt install python3.8

to finally check the version of python, execute this command.

hope that helps