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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 on_join(self, connection, event):
 """Handles the join event and greets everone :param connection: the connection with the event :type connection: :class:`irc.client.ServerConnection` :param event: the event to handle :type event: :class:`irc.client.Event` :returns: None """

        target = event.source
        self.privmsg(target, 'Hello %s!' % target)