[Tutor] Checking for the existence of a file

[Isaac Hall]

Hi python list!

I was wondering if someone could point me to some of the methods available 
for checking to see whether a file called aaaa.bbb exists through a python 
script.  The current method I use is:

if os.popen('ls '+filename).read()[:-1]==filename:
	exists=1
else:
	exists=0

however, sometimes, I run into a small problem with that....
sometimes, but not all the time, the script will tell me that the Index is 
out of range.  I am unable to replicate this error in the interactive 
interpreter, and I was wondering if there is a better way to do this.

Thanks

Ike

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