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From: Peter Otten <__peter__@web.de>
Subject: Re: problems with tkinter updates
Date: Thu, 26 Jan 2012 14:16:12 +0100
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:19486

woooee wrote:

[Peter Otten]
>>     line = next(infile, None)
>>     if line is not None:

> if line is not None: probably does not work the way you expect.  

It does what I expect.

> You might try
> if line.strip():
> Take a look at this quick example
> 
> test_lines = ["Number 1\n", "\n", ""]
> for ctr, line in enumerate(test_lines):
>     print ctr, line
>     if line is not None:
>          print "     not None"

Modify your example to

>>> test_lines = ["Number 1\n", "\n", ""]
>>> test_lines = iter(test_lines)
>>> while True:
...     line = next(test_lines, None)
...     if line is None:
...             print "we're done"
...             break
...     print repr(line)
...
'Number 1\n'
'\n'
''
we're done

and be enlightened ;)