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    <p>@Blair Conrad said static variables declared inside the class definition, but not inside a method are class or "static" variables:</p> <pre><code>&gt;&gt;&gt; class Test(object): ... i = 3 ... &gt;&gt;&gt; Test.i 3 </code></pre> <p>There are a few gotcha's here. Carrying on from the example above:</p> <pre><code>&gt;&gt;&gt; t = Test() &gt;&gt;&gt; t.i # static variable accessed via instance 3 &gt;&gt;&gt; t.i = 5 # but if we assign to the instance ... &gt;&gt;&gt; Test.i # we have not changed the static variable 3 &gt;&gt;&gt; t.i # we have overwritten Test.i on t by creating a new attribute t.i 5 &gt;&gt;&gt; Test.i = 6 # to change the static variable we do it by assigning to the class &gt;&gt;&gt; t.i 5 &gt;&gt;&gt; Test.i 6 &gt;&gt;&gt; u = Test() &gt;&gt;&gt; u.i 6 # changes to t do not affect new instances of Test # Namespaces are one honking great idea -- let's do more of those! &gt;&gt;&gt; Test.__dict__ {'i': 6, ...} &gt;&gt;&gt; t.__dict__ {'i': 5} &gt;&gt;&gt; u.__dict__ {} </code></pre> <p>Notice how the instance variable <code>t.i</code> got out of sync with the "static" class variable when the attribute <code>i</code> was set directly on <code>t</code>. This is because <code>i</code> was re-bound within the <code>t</code> namespace, which is distinct from the <code>Test</code> namespace. If you want to change the value of a "static" variable, you must change it within the scope (or object) where it was originally defined. I put "static" in quotes because Python does not really have static variables in the sense that C++ and Java do.</p> <p>Although it doesn't say anything specific about static variables or methods, the <a href="http://docs.python.org/tut/" rel="noreferrer">Python tutorial</a> has some relevant information on <a href="https://docs.python.org/2/tutorial/classes.html" rel="noreferrer">classes and class objects</a>. </p> <p>@Steve Johnson also answered regarding static methods, also documented under "Built-in Functions" in the Python Library Reference.</p> <pre><code>class Test(object): @staticmethod def f(arg1, arg2, ...): ... </code></pre> <p>@beid also mentioned classmethod, which is similar to staticmethod. A classmethod's first argument is the class object. Example:</p> <pre><code>class Test(object): i = 3 # class (or static) variable @classmethod def g(cls, arg): # here we can use 'cls' instead of the class name (Test) if arg &gt; cls.i: cls.i = arg # would the the same as Test.i = arg1 </code></pre> <p><a href="https://i.stack.imgur.com/xqnxe.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/xqnxe.jpg" alt="Pictorial Representation Of Above Example"></a></p>
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