code: def _estimate_expenses(self, num_workers, reward):
          ''' Returns tuple describing expenses:
          amount paid to workers
          amount paid to amazon'''
  
          # fee structure changed 07.22.15:
          # 20% for HITS with < 10 assignments
          # 40% for HITS with >= 10 assignments
          commission = 0.2
          if float(num_workers) >= 10:
              commission = 0.4
          work = float(num_workers) * float(reward)
          fee = work * commission
          return (work, fee, work+feef _estimate_expenses(self, num_workers, reward):
          ''' Returns tuple describing expenses:
          amount paid to workers
          amount paid to amazon'''
  
          # fee structure changed 07.22.15:
          # 20% for HITS with < 10 assignments
          # 40% for HITS with >= 10 assignments
          commission = 0.2
          if float(num_workers) >= 10:
              commission = 0.4
          work = float(num_workers) * float(reward)
          fee = work * commission
          return (work, fee, work+fee)
docs: Returns tuple describing expenses:
          amount paid to workers
          amount paid to amazon