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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 add_reactor(self, tag, reaction):
        '''
        Add a reactor
        '''
        reactors = self.list_all()
        for reactor in reactors:
            _tag = next(six.iterkeys(reactor))
            if _tag == tag:
                return {'status': False, 'comment': 'Reactor already exists.'}

        self.minion.opts['reactor'].append({tag: reaction})
        return {'status': True, 'comment': 'Reactor added.'}