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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(cls, action, suffix=None):
 """ Get or register a handler for the given action. :param func action: Callback that is called when invoking the Handler :param func suffix: Optional suffix for the handler's ID """

        action_id = _action_id(action, suffix)
        if action_id not in cls._HANDLERS:
            if LOG_OPTS['register']:
                hookenv.log('Registering reactive handler for %s' % _short_action_id(action, suffix),
                            level=hookenv.DEBUG)
            cls._HANDLERS[action_id] = cls(action, suffix)
        return cls._HANDLERS[action_id]