problem parsing lines in a file

[barronmo]

I'm having difficulty getting the following code to work.  All I want
to do is remove the '0:00:00' from the end of each line.  Here is part
of the original file:

3,3,"Dyspepsia NOS",9/12/2003 0:00:00
4,3,"OA of lower leg",9/12/2003 0:00:00
5,4,"Cholera NOS",9/12/2003 0:00:00
6,4,"Open wound of ear NEC*",9/12/2003 0:00:00
7,4,"Migraine with aura",9/12/2003 0:00:00
8,6,"HTN [Hypertension]",10/15/2003 0:00:00
10,3,"Imerslund syndrome",10/27/2003 0:00:00
12,4,"Juvenile neurosyphilis",11/4/2003 0:00:00
13,4,"Benign paroxysmal positional nystagmus",11/4/2003 0:00:00
14,3,"Salmonella infection, unspecified",11/7/2003 0:00:00
20,3,"Bubonic plague",11/11/2003 0:00:00

output = open('my/path/ProblemListFixed.txt', 'w')
for line in open('my/path/ProblemList.txt', 'r'):
     newline = line.rstrip('0:00:00')
     output.write(newline)
output.close()


This result is a copy of "ProblemList" without any changes made.  What
am I doing wrong?  Thanks for any help.

Mike