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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 register_action(self, action):
 """Register an action to be showed in the actions list. .. note:: A action can't be registered two times. If it happens, then an assert exception will be raised. :param action: The action to be registered. """

        assert action.value not in self.actions
        self.actions[action.value] = action