'Load the subsection grade from the persisted model.'

def init_from_model(self, student, model, course_structure, submissions_scores, csm_scores):

    for block in model.visible_blocks.blocks:
        self._compute_block_score(block.locator, course_structure, submissions_scores, csm_scores, block)
    self.graded_total = AggregatedScore(tw_earned=model.earned_graded, tw_possible=model.possible_graded, graded=True, first_attempted=model.first_attempted)
    self.all_total = AggregatedScore(tw_earned=model.earned_all, tw_possible=model.possible_all, graded=False, first_attempted=model.first_attempted)
    self._log_event(log.debug, u'init_from_model', student)
    return self
