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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 handle_joined(self, connection, event):
 """ Store join times for current nicknames when we first join. """

        nicknames = [s.lstrip("@+") for s in event.arguments()[-1].split()]
        for nickname in nicknames:
            self.joined[nickname] = datetime.now()