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copied!<p>Well, that was interesting enough for me to experiment a bit and I read through <a href="http://docs.python.org/reference/executionmodel.html" rel="nofollow noreferrer">http://docs.python.org/reference/executionmodel.html</a></p> <p>Then did some tinkering with your code here and there, this is what i could find:</p> <p>code:</p> <pre><code>import pprint def two(): from pprint import pprint print globals()['pprint'] pprint('Eggs') print globals()['pprint'] def main(): if 'pprint' in globals(): print 'pprint is in globals()' global pprint print globals()['pprint'] pprint.pprint('Spam') from pprint import pprint print globals()['pprint'] pprint('Eggs') def three(): print globals()['pprint'] pprint.pprint('Spam') if __name__ == '__main__': two() print('\n') three() print('\n') main() </code></pre> <p>output:</p> <pre><code><module 'pprint' from '/usr/lib/python2.5/pprint.pyc'> 'Eggs' <module 'pprint' from '/usr/lib/python2.5/pprint.pyc'> <module 'pprint' from '/usr/lib/python2.5/pprint.pyc'> 'Spam' pprint is in globals() <module 'pprint' from '/usr/lib/python2.5/pprint.pyc'> 'Spam' <function pprint at 0xb7d596f4> 'Eggs' </code></pre> <p>In the method <code>two()</code> <code>from pprint import pprint</code> but does not override the name <code>pprint</code> in <code>globals</code>, since the <code>global</code> keyword is <strong>not</strong> used in the scope of <code>two()</code>.</p> <p>In method <code>three()</code> since there is no declaration of <code>pprint</code> name in local scope it defaults to the global name <code>pprint</code> which is a module</p> <p>Whereas in <code>main()</code>, at first the keyword <code>global</code> <strong>is used</strong> so all references to <code>pprint</code> in the scope of method <code>main()</code> will refer to the <code>global</code> name <code>pprint</code>. Which as we can see is a module at first and is overriden in the <code>global</code> <code>namespace</code> with a method as we do the <code>from pprint import pprint</code> </p> <p>Though this may not be answering the question as such, but nevertheless its some interesting fact I think.</p> <p>=====================</p> <p><strong>Edit</strong> Another interesting thing.</p> <p>If you have a module say:</p> <p><code>mod1</code></p> <pre><code>from datetime import datetime def foo(): print "bar" </code></pre> <p>and another method say:</p> <p><code>mod2</code></p> <pre><code>import datetime from mod1 import * if __name__ == '__main__': print datetime.datetime.now() </code></pre> <p>which at first sight is seemingly correct since you have imported the module <code>datetime</code> in <code>mod2</code>.</p> <p>now if you try to run mod2 as a script it will throw an error:</p> <pre><code>Traceback (most recent call last): File "mod2.py", line 5, in <module> print datetime.datetime.now() AttributeError: type object 'datetime.datetime' has no attribute 'datetime' </code></pre> <p>because the second import <code>from mod2 import *</code> has overriden the name <code>datetime</code> in the namespace, hence the first <code>import datetime</code> is not valid anymore. </p> <p>Moral: Thus the order of imports, the nature of imports (from x import *) and the awareness of imports within imported modules - <strong>matters</strong>.</p>

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