'Prepares the fields for the grade record.'

@classmethod
def _prepare_params(cls, params):

    if (not params.get('course_id', None)):
        params['course_id'] = params['usage_key'].course_key
    params['course_version'] = (params.get('course_version', None) or '')
    params['visible_blocks'] = BlockRecordList.from_list(params['visible_blocks'], params['course_id'])
