擅长:python、mysql、java
<p>从<a href="https://docs.python.org/3/reference/expressions.html#boolean-operations" rel="nofollow">Python Documentation</a>:</p>
<blockquote>
<p>The expression x and y first evaluates x; if x is false, its value is
returned; otherwise, y is evaluated and the resulting value is
returned.</p>
</blockquote>
<p>因此,只要<code>x</code>是<code>False</code>,表达式的值就会是<code>False</code></p>