Newbie Text Processing Question

[gshepherd281 at earthlink.net]

Hi,

I'm a total newbie to Python so any and all advice is greatly
appreciated.

I'm trying to use regular expressions to process text in an SGML file
but only in one section.

So the input would look like this:

<ch-part no="I"><title>RESEARCH GUIDE
<sec-main no="1.01"><title>content
<para>content

<sec-main no="2.01"><title>content
<para>content


<ch-part no="II"><title>FORMS
<sec-main no="3.01"><title>content

<sec-sub1 no="1"><title>content
<para>content

<sec-sub2 no="1"><title>content
<para>content


and the output like this:

<ch-part no="I"><title>RESEARCH GUIDE
<sec-main no="1.01"><title>content
<biblio>
<para>content
</biblio>

<sec-main no="2.01"><title>content
<biblio>
<para>content
</biblio>

<ch-part no="II"><title>FORMS
<sec-main no="3.01"><title>content

<sec-sub1 no="1"><title>content
<para>content

<sec-sub2 no="1"><title>content
<para>content


But no matter what I try I end up changing the entire file rather than
just one part.

Here's what I've come up with so far but I can't think of anything
else.

***

import os, re
setpath = raw_input("Enter the path where the program should run: ")
print

for root, dirs, files in os.walk(setpath):
     fname = files
     for fname in files:
          inputFile = file(os.path.join(root,fname), 'r')
          line = inputFile.read()
          inputFile.close()


          chpart_pattern = re.compile(r'<ch-part
no=\"[A-Z]{1,4}\"><title>(RESEARCH)', re.IGNORECASE)

          while 1:
               if chpart_pattern.search(line):
                    line = re.sub(r"<sec-main
no=(\"[0-9]*.[0-9]*\")><title>(.*)", r"<sec-main
no=\1><title>\2\n<biblio>", line)
                    outputFile = file(os.path.join(root,fname), 'w')
                    outputFile.write(line)
                    outputFile.close()
                    break

               if chpart_pattern.search(line) is None:
                    print 'none'
                    break

Thanks,

Greg