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copied!<p>If I remember correctly, when Python switched to the new raise syntax in 2.5(?), they got rid of the <code>message</code> member in favor of an <code>args</code> tuple. For backward compatibility, <code>BaseException.message</code> is effectively the same thing as <code>BaseException.args[0] if BaseException.args else None</code>, but you shouldn't use it in new code.</p> <p>So, change <code>message</code> to either <code>args</code> (if you want all args) or <code>args[0]</code> (or, if you're worried there may be no args, the fancier version that protects against <code>()</code>), depending on which you want.</p> <p>The reason for this change is that with the new-style exceptions, there's no magic to <code>raise</code> or <code>except</code> anymore; you're just calling the exception class's constructor in the <code>raise</code> statement, and catching the exception in a variable in the <code>except</code> statement. So:</p> <pre><code>try: raise MyException('Out of cheese error', 42) except Exception as x: print x.args </code></pre> <p>This will print <code>('Out of cheese error', 42)</code>. If you only had <code>print x.message</code> you'd just get <code>'Out of cheese error'</code>. So, the Exception subclasses that used to have to do fancy things to carry around an error code as a separate member, etc., can be simplified; in fact, the whole thing comes down to this:</p> <pre><code>class BaseException(object): def __init__(self, *args): self.args = args </code></pre>

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