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<qhelp>

<overview>

<p>In Python, <code>return</code> and <code>yield</code> statements and the <code>yield from</code>

expression can only be used within a function. Using them outside a function or a class

method results in a <code>SyntaxError</code> at runtime.</p>

</overview>

<recommendation>

<p>Using these elements outside a function or a class method usually indicates an error in the logic.

Consequently, it is not possible to suggest a general fix.</p>

</recommendation>

<example>

<p>In this example, a <code>return</code> statement is used outside a class method in a class and

a <code>yield</code> statement is used outside a function in a scope of a module which would result

in a <code>SyntaxError</code> when running this code.

In this example, the invalid class could be corrected by placing the <code>return</code> statement

in a class method, or by refactoring the class into a function. The invalid <code>yield</code> statement

could become part of a new generator function containing the <code>for</code> loop.</p>

<sample src="ReturnOrYieldOutsideFunction.py" />

</example>

<references>

<li>Python reference: <a href="https://docs.python.org/3.7/reference/simple_stmts.html#the-return-statement">

The return statement</a>.</li>

<li>Python reference: <a href="https://docs.python.org/3.7/reference/simple_stmts.html#yield">

The yield statement</a>.</li>

<li>Python PEP-380: <a href="https://docs.python.org/3/whatsnew/3.3.html#pep-380">

The yield from expression</a>.</li>

</references>

</qhelp>