def organizeUserPerformanceByTimestampAndDetermineTestDifficulty(self,testType,userOntologyAlias,currentTimestamp,lookBackTimeStamp,res,modifier1,modifier2):
    noUserPerformanceRecordsExist=False;
    chosenDif="1"
    userPerformanceReq=userPerformanceCognitveTestsSrvRequest()
    userPerformanceReq.test_type=testType
    userPerformanceReq.ontology_alias=userOntologyAlias
    serv_topic = rospy.get_param('rapp_knowrob_wrapper_user_performance_cognitve_tests')
    knowrob_service = rospy.ServiceProxy(serv_topic, userPerformanceCognitveTestsSrv)
    userPerformanceResponse = knowrob_service(userPerformanceReq)
    
    userPerfOrganizedByTimestamp=[]
    if(userPerformanceResponse.success!=True):
      res.trace.extend(userPerformanceResponse.trace)
      res.trace.append("KnowRob wrapper returned no performance records for this user.. will start with a a difficulty setting of 1")
      noUserPerformanceRecordsExist=True
    else:
      userPerfOrganizedByTimestamp=self.organizeUserPerformance(userPerformanceResponse)
      for k, v in userPerfOrganizedByTimestamp.items():
        if(k-currentTimestamp>lookBackTimeStamp):
          del userPerfOrganizedByTimestamp[k]
        else:
          break

      userScore=self.calculateUserScore(userPerfOrganizedByTimestamp)
      res.trace.append("user score :"+str(userScore))
      if(userScore==0):
        chosenDif="1"
      elif(userScore<modifier1):
        chosenDif="1"
      elif(userScore<modifier2):
        chosenDif="2"
      else:   #(userScore>0.75*3*100)
        chosenDif="3"
    res.trace.append("Chosen Diff :"+chosenDif)
    return chosenDif,noUserPerformanceRecordsExist,userPerfOrganizedByTimestamp
    
  ## @brief Gets the cognitive tests of the given type and difficulty available in the ontology  
  # @param testType [string] The test type (category)
  # @param userLanguage [string] The user's language
  # @param chosenDif [string] The difficulty setting
  # @param res [rapp_platform_ros_communications::testSelectorSrvResponse::Response&] The output arguments of the service as defined in the testSelectorSrv
  #
  # @return res [rapp_platform_ros_communications::testSelectorSrvResponse::Response&] The output arguments of the service as defined in the testSelectorSrv
  # @return bool [bool] True if a non recoverable error occured, and the service must immediately return with an error report
  # @return testsOfTypeOrdered [dict] The cognitive tests of the given type and difficulty setting
dataset/ETHPy150Open rapp-project/rapp-platform/rapp_cognitive_exercise/src/test_selector.py/TestSelector.organizeUserPerformanceByTimestampAndDetermineTestDifficulty/swapped operands of `-`