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copied!<p>Since you're talking about javascript and <code>hasattr</code>, I'm guessing this is a situation where <code>variable</code> is undefined. In Python, <code>hasattr</code> doesn't test for the presence of dictionary keys, it only tests for the presence of object attributes. Furthermore, there is no simpler way than <code>hasattr</code> to test whether an object has an attribute in Python, because unlike in javascript, variable names <em>must</em> be defined to be used. Therefore, to refer to a variable name that may or may not be defined, you must use a string. </p> <p>That said, you could use the ternary operator + <code>hasattr</code> to write the test in one line:</p> <pre><code>>>> class F(object): ... pass ... >>> f = F() >>> f.foo = 5 >>> f.bar if hasattr(f, 'bar') else 10 10 >>> f.foo if hasattr(f, 'foo') else 10 5 </code></pre> <p>This works because <code>f.foo</code> isn't even evaluated if <code>hasattr</code> returns <code>False</code>.</p> <p>You could also define <code>f.foo = None</code> and use <code>or</code> as <a href="https://stackoverflow.com/questions/6697816/python-version-of-jss-x-variable-default-variable/6697904#6697904">Wooble</a> suggests in his comment.</p> <p>To test whether a key is in a dictionary, say <code>if k in d:</code>, and to get a default value if <code>k</code> isn't in the dictionary, if that's what you want, see <a href="https://stackoverflow.com/questions/6697816/python-version-of-jss-x-variable-default-variable/6697836#6697836">S.Lott's answer</a>.</p>

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