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<qhelp>

<overview>

<p>Iterator classes (classes defining a <code>__next__</code> method) should have an <code>__iter__</code> method that returns the iterator itself.

This ensures that the object is also an iterable; and behaves as expected when used anywhere an iterator or iterable is expected, such as in <code>for</code> loops.

</p>

</overview>

<recommendation>

<p>Ensure that the <code>__iter__</code> method returns <code>self</code>, or is otherwise equivalent as an iterator to <code>self</code>.</p>

</recommendation>

<example>

<p>In the following example, the <code>MyRange</code> class's <code>__iter__</code> method does not return <code>self</code>.

This would lead to unexpected results when used with a <code>for</code> loop or <code>in</code> statement.</p>

<sample src="examples/IterReturnsNonSelf.py" />

</example>

<references>

<li>Python Language Reference: <a href="http://docs.python.org/3/reference/datamodel.html#object.__iter__">object.__iter__</a>.</li>

<li>Python Standard Library: <a href="http://docs.python.org/3/library/stdtypes.html#typeiter">Iterators</a>.</li>

</references>

</qhelp>