Score for Twinkle Twinkle Little Stars
https://www.music-for-music-teachers.com/twinkle-twinkle.html

Score for Happy Birthday To You
https://musescore.com/user/27657013/scores/5282628

Mary had a little lamb
Heman Gohil
https://musescore.com/user/29659593/scores/5226751

CC 4.0 Attribution
https://creativecommons.org/licenses/by/4.0/

Piano Sounds
http://theremin.music.uiowa.edu/MISpiano.html

Fur Elise
https://musescore.com/classicman/scores/33816

To use
python main.py
(Raspberry Pi)
sudo -E python3 main.py

Doesn't work on python2 because it requires the simpleaudio library

Replace BtnInput with KeyboardInput if you want to control using your computer's keyboard
(and remove all the references to RPi.GPIO and Adafruit)

MIT License
Copyright 2019 Guanqun Wu, Zhaopeng Xu

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and 
associated documentation files (the "Software"), to deal in the Software without restriction, including 
without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 
copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the 
following conditions:

The above copyright notice and this permission notice shall be included in all copies or 
substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, 
INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE 
AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 
DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.