how to open some specific files using python
===

I have a couple of files named as yyyymmdd-hhmmss.csv.gz. Now I want to open each day's first file from 02am, do some process, one by one.

My files are: 
    
    ...
    20120706-015923.txt
    20120706-015934.txt 
    20120706-020008.txt
    20120706-020030.txt
    ...
    20120707-015934.txt
    20120707-020005.txt
    20120707-020015.txt
    ...

So I want to go through the file name in this folder first, to find 20120706-020008.txt which is the first file from the 02am that day, then I had a script to read all the lines and do some process. My problem is, how to tell this script to find these files?
20120706-020008.txt, 20120707-020015.txt,20120708-02....
