<!DOCTYPE qhelp PUBLIC

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"qhelp.dtd">

<qhelp>

<overview>

<p>This global variable may not be defined.

If this code is executed and the variable is undefined then a <code>NameError</code> will occur.

</p>

</overview>

<recommendation>

<p>Check that the name of the global variable is not a typographic error. If the name is correct

then define the variable or import the module that defines the function or method.</p>

<p>If it is expected this variable will be initialized from another module before it is used, then the <code>NameError</code> may not occur.

Nonetheless, the code will be more robust and clearer if the variable is set to a default value in its own module.

</p>

</recommendation>

<example>

<p>The following examples show two different examples of undefined "global variables".</p>

<sample src="UndefinedGlobal.py" />

</example>

<references>

<li>Python Standard Library: <a href="https://docs.python.org/library/exceptions.html#exceptions.NameError">NameError</a>.</li>

<li>The Python Tutorial: <a href="http://docs.python.org/2/tutorial/modules.html">Modules</a>.</li>

</references>

</qhelp>