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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def start(self):
 """Log start event."""

        today = time.time()
        yesterday = today - 86400
        today = time.localtime(today)
        yesterday = time.localtime(yesterday)

        link = configuration.Url

        self.rssfn = self.getFilename()

        if os.path.exists(self.rssfn):
            self.newfile = False
            self.rss = rss.parseFeed(self.rssfn, yesterday)
        else:
            self.newfile = True
            self.rss = rss.Feed('Daily Dosage', link, 'Comics for %s' % time.strftime('%Y/%m/%d', today))