def do_default(value, default_value=u'', boolean=False):
    if (boolean and not value) or isinstance(value, Undefined):
        return default_value
    return value
Returns the SQL for starting a new savepoint. Only required if the
dataset/ETHPy150Open IanLewis/kay/kay/lib/jinja2/filters.py/do_default--crossover with--dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.4/django/db/backends/__init__.py/BaseDatabaseOperations.savepoint_create_sql