clean up class and remove commented code
clean up class and remove commented code

alphagov/trade-tariff-backend,alphagov/trade-tariff-backend,bitzesty/trade-tariff-backend,bitzesty/trade-tariff-backend,leftees/trade-tariff-backend,leftees/trade-tariff-backend,alphagov/trade-tariff-backend,bitzesty/trade-tariff-backend,leftees/trade-tariff-backend