Moves code into a main() function to avoid global variables.
Moves code into a main() function to avoid global variables.

Smelly-London/Smelly-London,jen-thomas/smelly_london,Smelly-London/Smelly-London,jen-thomas/smelly_london,Smelly-London/datavisualisation,mgrazebrook/smelly_london,Smelly-London/Smelly-London,Smelly-London/Smelly-London,Smelly-London/datavisualisation,mgrazebrook/smelly_london