'Begin a bulk operation on course_key.'

def _begin_bulk_operation(self, course_key, ignore_case=False):

    bulk_ops_record = self._get_bulk_ops_record(course_key, ignore_case)
    bulk_ops_record.nest()
    if bulk_ops_record.is_root:
        self._start_outermost_bulk_operation(bulk_ops_record, course_key, ignore_case)
