擅长:python、mysql、java
<p>首先,你不应该有<code>requiredFields = ('single element')</code>——如果你想要一个元组,你应该写<code>requiredFields = ('single element',)</code>。在</p>
<p>但假设您无法控制您的输入,最常见的测试方法是:</p>
<pre><code>if isinstance(requiredFields, basestring):
# requiredFields is a string
else:
# requiredFields is iterable
</code></pre>