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<overview>

<p>When handling an exception, Python searches the except blocks in source code order

until it finds a matching <code>except</code> block for the exception.

An except block, <code>except E:</code>, specifies a class <code>E</code> and will match any

exception that is an instance of <code>E</code>.

</p>

<p>

If a more general except block precedes a more specific except block,

then the more general block is always executed and the more specific block is never executed.

An except block, <code>except A:</code>, is more general than another except block, <code>except B:</code>,

if <code>A</code> is a super class of <code>B</code>.

</p>

<p>

For example:

<code>except Exception:</code> is more general than <code>except Error:</code> as <code>Exception</code>

is a super class of <code>Error</code>.

</p>

</overview>

<recommendation>

<p>Reorganize the <code>except</code> blocks so that the more specific <code>except</code>

is defined first. Alternatively, if the more specific <code>except</code> block is

no longer required, then it should be deleted.</p>

</recommendation>

<example>

<p>In the following example, the <code>except Exception:</code> will handle <code>AttributeError</code> preventing the

subsequent handler from ever executing.</p>

<sample src="IncorrectExceptOrder.py" />

</example>

<references>

<li>Python Language Reference: <a href="http://docs.python.org/3/reference/compound_stmts.html#try">The try statement</a>,

<a href="http://docs.python.org/3/reference/executionmodel.html#exceptions">Exceptions</a>.</li>

</references>

</qhelp>