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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 parse_feeds(self, message_channel=True):
 """ Iterates through each of the feed URLs, parses their items, and sends any items to the channel that have not been previously been parsed. """

        if parse:
            for feed_url in self.feeds:
                feed = parse(feed_url)
                for item in feed.entries:
                    if item["id"] not in self.feed_items:
                        self.feed_items.add(item["id"])
                        if message_channel:
                            message = self.format_item_message(feed, item)
                            self.message_channel(message)
                            return