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    <p>The article glosses over some details. When you have questions like this, it's time to turn to an authoritative source, which in this case is The Python Language Reference, section <a href="http://docs.python.org/2/reference/datamodel.html#the-standard-type-hierarchy" rel="nofollow">3.2. The standard type hierarchy</a>, which contains an entry for classes which states (my emphasis):</p> <blockquote> <p>A class has a namespace implemented by a dictionary object. Class attribute references are translated to lookups in this dictionary, e.g., <code>C.x</code> is translated to <code>C.__dict__["x"]</code> (although for new-style classes in particular there are a number of hooks which allow for other means of locating attributes). <strong>When the attribute name is not found there, the attribute search continues in the base classes</strong>.</p> </blockquote> <p>This is describing attribute lookup for classes, not class instances, and i believe it explains what is happening in your code.</p> <p>For completeness, here's what the next entry, about class instances, says:</p> <blockquote> <p>A class instance has a namespace implemented as a dictionary which is the first place in which attribute references are searched. When an attribute is not found there, and the instance’s class has an attribute by that name, the search continues with the class attributes.</p> </blockquote> <p>I take "the search continues with the class attributes" as meaning "repeat the procedure given for classes", ie search the base classes. Inheritance would be rather less useful if it didn't!</p> <p>The article you link to explains attribute lookup for class instances, but it doesn't say anything about attribute lookup for classes. Because it doesn't, it gives the impression that it works the same way, which is not the case.</p>
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    1. COTom thanks for looking at this question, may be I am reading (understanding it incorrectly) but this is what the line in article means. Bases of the Object (Leaf in this example) is 'type' and it's base is 'object' which doesn't have any further base class. Superb in this case is not the base of object's class or the base of base of object's class, it's the base of the base of the object itself.
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    2. CO@AccEnq: You're absolutely right. I actually misread your question, and thought you were talking about attribute lookup in a class instance. That was careless of me - my apologies. I have rewritten the answer to refer to the Python language reference, which explains this.
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    3. COCan't thank you enough.
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