code: def get_one(self, process_name, timeperiod):
          
          collection_name = self._get_job_collection_name(process_name)
          collection = self.ds.connection(collection_name)
          document = collection.find_one({job.PROCESS_NAME: process_name, job.TIMEPERIOD: timeperiod})
  
          if document is None:
              raise LookupError('MongoDB has no job record in collection {0} for {1}@{2}'
                                .format(collection, process_name, timeperiod))
          return Job.from_json(document)
docs: method finds a single job record and returns it to the caller