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copied!<p>If you want to create a class variable, you must to declare it outside any class methods (but still inside the class definition):</p> <pre><code>class Example(object): somevariable = 'class variable' </code></pre> <p>With this you can now access your class variable.</p> <pre><code>>> Example.somevariable 'class variable' </code></pre> <hr> <p>The reason why your example isn't working is because you are assigning a value to an <code>instance</code> variable. </p> <p>The difference between the two is that a <code>class</code> variable is created as soon as the class object is created. Whereas an <code>instance</code> variable will be created once the object has been <em>instantiated</em> and only after they have been assigned to. </p> <pre><code>class Example(object): def doSomething(self): self.othervariable = 'instance variable' >> foo = Example() </code></pre> <p>Here we created an instance of <code>Example</code>, however if we try to access <code>othervariable</code> we will get an error:</p> <pre><code>>> foo.othervariable AttributeError: 'Example' object has no attribute 'othervariable' </code></pre> <p>Since <code>othervariable</code> is assigned inside <code>doSomething</code> - and we haven't called ityet -, it does not exist.</p> <pre><code>>> foo.doSomething() >> foo.othervariable 'instance variable' </code></pre> <hr> <p><code>__init__</code> is a special method that automatically gets invoked whenever class instantiation happens. </p> <pre><code>class Example(object): def __init__(self): self.othervariable = 'instance variable' >> foo = Example() >> foo.othervariable 'instance variable' </code></pre>

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