code: def reqScannerSubscription(
              self, subscription: ScannerSubscription,
              scannerSubscriptionOptions: List[TagValue] = None,
              scannerSubscriptionFilterOptions:
              List[TagValue] = None) -> ScanDataList:
          
          reqId = self.client.getReqId()
          dataList = ScanDataList()
          dataList.reqId = reqId
          dataList.subscription = subscription
          dataList.scannerSubscriptionOptions = scannerSubscriptionOptions
          dataList.scannerSubscriptionFilterOptions = \
              scannerSubscriptionFilterOptions
          self.wrapper.startSubscription(reqId, dataList)
          self.client.reqScannerSubscription(
              reqId, subscription, scannerSubscriptionOptions,
              scannerSubscriptionFilterOptions)
          return dataList
docs: Subscribe to market scan data.
  
          https://interactivebrokers.github.io/tws-api/market_scanners.html
  
          Args:
              subscription: What to scan for.
              scannerSubscriptionOptions: Unknown.
              scannerSubscriptionFilterOptions: Unknown.