Installing Python3.8 along with Pip3 in Ubuntu 18.04 | Change Default python3 in your system.

In this video you'll learn how to install the latest version of Python in your Ubuntu and pip3. And change the default Python3 version in your system.

Here is the list of commands you gonna need for this setup:
1) sudo apt update

2) sudo apt install software-properties-common

3) sudo add-apt-repository ppa:deadsnakes/ppa

4) sudo apt install python3.8

5) python3.8 --version

6) sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.6 1

7) sudo update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.8 2

8) sudo update-alternatives --config python3

************************* Select python3.8 ****************************

9) python3 --version

10) sudo apt-get install python3-pip

11) pip3 --version

###### Installing the libraries for python ######

12) sudo pip3 install numpy
13) sudo pip3 install matplotlib
14) sudo pip3 install scipy

For any question related to this set up asked me in the comment box and I'll reply them as soon as possible.

[xNeitorx]

NAH BRO YOU'RE THE F INDIAN GOD OF UBUNTU THANK U SO MUCH IT'S EXACTLY WHAT I WAS SEARCHING FOR SO LONG <3 <3 <3

[petermusau]

That was extremely helpful. I remember I previously broke my system, I installed python3.9 and remoed default python3.8, now I know that is wrong.
Kindly the pip3 is still previous one and when I upgrade it, it tells me pip3-21.0.1 installed successfully but can't uninstall pip3-20.0.1, no such directory, yet it is the one I use.
Plz, any suggestion would be very much appreciated

[_whitecatfullgrown]

I try this and then got error while "sudo apt update"
The error is "ImportError : no module named apt_pkg"