code: def remainingBillingInterval(self):
          
          if self.launchTime:
              now = datetime.datetime.utcnow()
              delta = now - parse_iso_utc(self.launchTime)
              return 1 - delta.total_seconds() / 3600.0 % 1.0
          else:
              return 1
docs: If the node has a launch time, this function returns a floating point value
          between 0 and 1.0 representing how far we are into the
          current billing cycle for the given instance. If the return value is .25, we are one
          quarter into the billing cycle, with three quarters remaining before we will be charged
          again for that instance.
  
          Assumes a billing cycle of one hour.
  
          :return: Float from 0 -> 1.0 representing percentage of pre-paid time left in cycle.