Opening this bug at Ben Finney's request.  See https://groups.google.com/forum/?fromgroups#!topic/comp.lang.python/wmDUrpW2ZCU for the full thread discussing the problem.  Here's a significant excerpt:

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The tutorial is misleading on this. It it says plainly: 

    A module can contain executable statements as well as function 
    definitions. […] They are executed only the *first* time the module 
    is imported somewhere. 

    <URL:http://docs.python.org/tutorial/modules.html> 

but it doesn't make clear that a module can exist in the ‘sys.modules’ 
list multiple times under different names. 
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Also note:

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The footnote to that is wrong too: 

> [1]        In fact function definitions are also ‘statements’ that are ‘executed’; the execution of a module-level function enters the function name in the module’s global symbol table. 

I think what it's supposed to say is "... the execution of a module-level def statement ..." 
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