code: def get_submission_and_student(uuid, read_replica=False):
      
      # This may raise API exceptions
      submission = get_submission(uuid, read_replica=read_replica)
  
      # Retrieve the student item from the cache
      cache_key = "submissions.student_item.{}".format(submission['student_item'])
      try:
          cached_student_item = cache.get(cache_key)
      except Exception:
          # The cache backend could raise an exception
          # (for example, memcache keys that contain spaces)
          logger.exception("Error occurred while retrieving student item from the cache")
          cached_student_item = None
  
      if cached_student_item is not None:
          submission['student_item'] = cached_student_item
      else:
          # There is probably a more idiomatic way to do this using the Django REST framework
          try:
              student_item_qs = StudentItem.objects
              if read_replica:
                  student_item_qs = _use_read_replica(student_item_qs)
  
              student_item = student_item_qs.get(id=submission['student_item'])
              submission['student_item'] = StudentItemSerializer(student_item).data
              cache.set(cache_key, submission['student_item'])
          except Exception as ex:
              err_msg = "Could not get submission due to error: {}".format(ex)
              logger.exception(err_msg)
              raise SubmissionInternalError(err_msg)
  
      return submission
docs: Retrieve a submission by its unique identifier, including the associated student item.
  
      Args:
          uuid (str): the unique identifier of the submission.
  
      Kwargs:
          read_replica (bool): If true, attempt to use the read replica database.
              If no read replica is available, use the default database.
  
      Returns:
          Serialized Submission model (dict) containing a serialized StudentItem model
  
      Raises:
          SubmissionNotFoundError: Raised if the submission does not exist.
          SubmissionRequestError: Raised if the search parameter is not a string.
          SubmissionInternalError: Raised for unknown errors.