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<qhelp>

<overview>

<p> The <code>exit</code> and <code>quit</code> "functions" are actually <code>site.Quitter</code> objects and

are loaded, at interpreter start up, from <code>site.py</code>.

However, if the interpreter is started with the <code>-S</code> flag, or a custom <code>site.py</code>

is used then <code>exit</code> and <code>quit</code> may not be present.

</p>

</overview>

<recommendation>

<p> Replace uses of <code>exit()</code> and <code>quit()</code> with <code>sys.exit()</code> which is

built into the interpreter and is guaranteed to be present.</p>

</recommendation>

<example>

<p>In this example, <code>exit()</code> is used and will fail if the interpreter is passed the <code>-S</code> option.</p>

<sample src="ExitUsed.py" />

<p>In this example, <code>sys.exit()</code> is used and will behave the same regardless of the interpreter options.</p>

<sample src="SysExitUsed.py" />

</example>

<references>

<li>Python Documentation: <a href="https://docs.python.org/using/cmdline.html#cmdoption-S">Command line and environment</a>.</li>

<li>Python Documentation: <a href="https://docs.python.org/library/site.html#module-site">Site-specific configuration hook</a>.</li>

</references>

</qhelp>