A simple python script from which you can download the songs by just entering the name. You can also download by entering a list of name, youtube link or list of youtube links.
You can try that online. Here is the link -> http://mp3.amanroy.me
Make sure you have python and youtube-dl installed.
Install youtube-dl for UBUNTU
$ sudo apt-get install youtube-dl
Install youtube-dl for windows
For windows download youtube-dl.exe file and copy it in the directory.
For other operating systems
This program is tested on Ubuntu 16.04 LTS
Downloading copyrighted material may be illegal in your country. Use at your own risk.