[Tutor] Another fine mess

[GNULinuxGeek]

All,

I posted some time back for another task.

Have a new task now.  You were all so kind with advice that I thought I 
might check my thoughts on this.

Being an old guy and a newbie to Python is the double-whammy, but here goes:

I get a CSV file with ~26 fields and ~7000 records.  This data needs to 
be parsed based on specific field values.

So, here is my "draft" set of steps that I think need to be performed.

   1. Select the "file" of data
   2. Clean the data with "strip" to make sure there is no extraneous
      whitespace
   3. Write the file back to a temp file.
   4. On the new file, select records based on the value of some of the
      fields (like a "sort on" in a spreadsheet.
   5. Parse to obtain the matching records
   6. Do a little math based on how many records and the data in one
      field (success vs. fail)
   7. Output the results of the math so it can be used in a spreadsheet
      to make cute graphics.

We have a PERL guy in the division, but I am trying to use Python only 
to get this done.  My question is

"What is a good way to read and process the lines of the CSV file?" 
Do I pull them in one line at a time and write them to an output file? 
Do I read the whole shebang, clean the data and write an output file, 
then re-open the cleaned file?


Thanking you all prematurely,

Regards,

Ralph