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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 get_bot(self, bot_label):
 """ Import all bots and returns a bot class for the given label. Raise LookupError if no bot exists with this label. """

        self.check_bots_ready()
        try:
            return self.bots[bot_label]
        except KeyError:
            message = "No installed bot with label '%s'." % bot_label
            for bot_cls in self.get_bots():
                if bot_cls.name == bot_label:
                    message += " Did you mean '%s'?" % bot_cls.label
                    break
            raise LookupError(message)