code: def update_memo(self, task_id, task, r):
          
          if not self.memoize or not task['memoize']:
              return
  
          if task['hashsum'] in self.memo_lookup_table:
              logger.info('Updating appCache entry with latest %s:%s call' %
                          (task['func_name'], task_id))
              self.memo_lookup_table[task['hashsum']] = r
          else:
              self.memo_lookup_table[task['hashsum']] = r
docs: Updates the memoization lookup table with the result from a task.
  
          Args:
               - task_id (int): Integer task id
               - task (dict) : A task dict from dfk.tasks
               - r (Result future): Result future
  
          A warning is issued when a hash collision occurs during the update.
          This is not likely.