def save():
    return 42

def save_user():
    return save()

def discard_user():
    save()
    return 0

def overwrite_user():
    result = save()
    result = 0
    return result

def bad_default(items=[]):
    return items

def fresh_default(items=None):
    return [] if items is None else items

class Writer:
    def write(self):
        return save()
    def close(self):
        pass

class ReadOnly:
    def read(self):
        return 1
