code: def getNextJob(self):
      ret = None
  
      with self.__lock:
          # Get the next set of parameters.
          params = [
              p.args
              for p in self.__paramSource.getNext(self.__batchSize)
          ]
  
          # Map the active job
          if len(params):
              ret = Job(params)
              self.__activeJobs[ret.getId()] = ret
  
      return serialization.dumps(ret)
  
imports: import threading
  import time
  from six.moves import xmlrpc_server
  import pyalgotrade.logger
  from pyalgotrade.optimizer import base
  from pyalgotrade.optimizer import serialization
label_desc: Use image node_id 4 for calling the Server obj's underlying member method code with example usage: obj.getNextJob() and returns: serialization