How to add the source of Ubuntu Tweak

open your terminal, first import the key:
sudo apt-key adv --recv-keys --keyserver keyserver.ubuntu.com FE85409EEAB40ECCB65740816AF0E1940624A220
type the command to run gedit(or other editor in your opinion) to modify the sources.list:
sudo gedit /etc/apt/sources.list
And put the two line into it(If you are using Ubuntu 8.04 Hardy or early) :
deb http://ppa.launchpad.net/tualatrix/ppa/ubuntu hardy main
deb-src http://ppa.launchpad.net/tualatrix/ppa/ubuntu hardy main
Or Ubuntu 8.10 Intrepid:
deb http://ppa.launchpad.net/tualatrix/ppa/ubuntu intrepid main
deb-src http://ppa.launchpad.net/tualatrix/ppa/ubuntu intrepid main
Or Ubuntu 9.04 Jaunty:
deb http://ppa.launchpad.net/tualatrix/ppa/ubuntu jaunty main
deb-src http://ppa.launchpad.net/tualatrix/ppa/ubuntu jaunty main
Or Ubuntu 9.10 Karmic:
deb http://ppa.launchpad.net/tualatrix/ppa/ubuntu karmic main
deb-src http://ppa.launchpad.net/tualatrix/ppa/ubuntu karmic main
Then update the source and install or upgrade Ubuntu Tweak:
sudo apt-get update
sudo apt-get install ubuntu-tweak

Install Pytube in Ubuntu

Install Pytube in Ubuntu
Method 1
First you need to edit /etc/apt/sources.list file:

sudo gedit /etc/apt/sources.list

Add the following line:

deb http://www.bashterritory.com/pytube/releases/ /

Save and exit the file
Now you need to update the source list using the following command:

sudo aptitude update

Install pytube install in ubuntu:

sudo aptitude install pytube

This will complete the pytube installation.

Method 2
You can download pytube .deb package from here
New ubuntu installer download from here
after downloading you need to install this file using the following command:

sudo dpkg -i pytube_0.0.11.4~getdeb1_all.deb

This will complete the installation.
Note: This application requires ffmpeg compiled with mp4 and 3gp support wich can be found on the Medibuntu repository.