PYTHON - Converting datetime string to integer (seconds ) then adding ms
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I am writing a program that essentially pulls a line out of a logfile, parses it, and returns the parsed data back in a simplified form. My main problem currently is the method in which I should parse my datetime stirngs. Here's an example of a line from the log. 

Example of Logfile:

    2012-06-12 14:02:16,341 [main] INFO ---
    2012-06-12 14:02:16,509 [main] INFO ---
    2012-06-12 14:02:17,000 [main] INFO ---
    2012-06-12 14:02:17,112 [main] INFO ---
    2012-06-12 14:02:20,338 [main] INFO ---
    2012-06-12 14:02:21,813 [main] INFO ---

My code to parse SO FAR ( very rough ):

    class LogLine:
    
        SEVERITIES = ['EMERG','ALERT','CRIT','ERR','WARNING','NOTICE','INFO','DEBUG']
        severity = 1
    
        def __init__(self, line):
            try:
                t, s, self.filename, n, self.message =
                    re.match(r"^(\d\d\d\d-\d\d-\d\d[ \t]\d\d:\d\d:\d\d,\d\d\d)", line)
                self.line = int(n)
                self.sev = self.SEVERITIES.index(s)
                self.time = time.strptime(t)
    
    
        def get_t(self):
            return
    
        def get_severity(self):
            return self.SEVERITIES.index(self)
        def get_message(self):
            return
        def get_filename(self):
            return
        def get_line(self):
            return

So basically (if you weren't able to deduce from my terrible code) I am parsing the string using a regular expression to obtain the datetime. I also have been reading about strptime as a possible solution to this as well. ULTIMATELY, I need to parse the datetime into milliseconds and then add it to the milliseconds integer in the datetime (separated by comma) 


I'm sure this question is extremely convoluted and I apologize in advance. Thank you for your help. 
