python loop back to start

1def main(): #defines the area in indents that will be triggered with main()#
2  print('hi')
3  yn = input('Wanna loop back to the start? ')
4  if yn = 'yes':
5    main() #loops back to where we defined main#
6    
7main() #This starts the main loop, without this, main would just be defined but not run#