擅长:python、mysql、java
<p>你可以上一节课:</p>
<pre><code>class Brand(object):
def __init__(*models, default=None):
self.models = *models
self.default = default
assert default is None or default in models
</code></pre>
<p>然后使用它:</p>
<pre><code>SUZUKI = Brand('model_1', 'model_2', 'model_3', default='model_1')
FERRARI = Brand('model_1', 'model_2', default='model_2')
PORSCH = Brand('model_1', 'model_2', default=None)
</code></pre>