擅长:python、mysql、java
<p>而不是尝试</p>
<pre><code>self.type = NULL
</code></pre>
<p>以<a href="https://stackoverflow.com/users/1377864/yaroslav-admin">Yaroslav Admin suggested</a>身份尝试</p>
<pre><code>self.type = None
</code></pre>
<p>因为Python的NULL等价物是None。</p>