def calculate(self, logid, work):
    print('calculate(%d, %r)' % (logid, work))

    if work.op == Operation.ADD:
      val = work.num1 + work.num2
    elif work.op == Operation.SUBTRACT:
      val = work.num1 - work.num2
    elif work.op == Operation.MULTIPLY:
      val = work.num1 * work.num2
    elif work.op == Operation.DIVIDE:
      if work.num2 == 0:
        x = InvalidOperation()
        x.what = work.op
        x.why = 'Cannot divide by 0'
        raise x
      val = work.num1 / work.num2
    else:
      x = InvalidOperation()
      x.what = work.op
      x.why = 'Invalid operation'
      raise x

    log = SharedStruct()
    log.key = logid
    log.value = '%d' % (val)
    self.log[logid] = log

    return val

    def calculate(self, logid, work):
        print("calculate({}, {})".format(logid, work))

        if work.op == Operation.ADD:
            val = work.num1 + work.num2
        elif work.op == Operation.SUBTRACT:
            val = work.num1 - work.num2
        elif work.op == Operation.MULTIPLY:
            val = work.num1 * work.num2
        elif work.op == Operation.DIVIDE:
            if work.num2 == 0:
                x = InvalidOperation()
                x.whatOp = work.op
                x.why = "Cannot divide by 0"
                raise x
            val = work.num1 / work.num2
        else:
            x = InvalidOperation()
            x.whatOp = work.op
            x.why = "Invalid operation"
            raise x

        log = SharedStruct()
        log.key = logid
        log.value = '%d' % (val)
        self.log[logid] = log
        return val

    def calculate(self, logid, work):
        """By default, this method runs in the server's executor threads."""
        print('calculate(%d, %r)' % (logid, work))

        # Calculate the 10000000th prime number first, it takes 1 second.
        end = time.time() + 1
        while True:
            now = time.time()
            if now >= end:
                break

        if work.op == Operation.ADD:
            val = work.num1 + work.num2
        elif work.op == Operation.SUBTRACT:
            val = work.num1 - work.num2
        elif work.op == Operation.MULTIPLY:
            val = work.num1 * work.num2
        elif work.op == Operation.DIVIDE:
            if work.num2 == 0:
                x = InvalidOperation()
                x.what = work.op
                x.why = 'Cannot divide by 0'
                raise x
            val = work.num1 // work.num2
        else:
            x = InvalidOperation()
            x.what = work.op
            x.why = 'Invalid operation'
            raise x

        log = SharedStruct()
        log.key = logid
        log.value = '%d' % (val)
        self.log[logid] = log

        return val