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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 set_start_state(self, state):
 """Sets the start state of a container state :param state: The state_id of a state or a direct reference ot he state (that was already added to the container) that will be the start state of this container state. """

        if state is None:
            self.start_state_id = None
        elif isinstance(state, State):
            self.start_state_id = state.state_id
        else:
            self.start_state_id = state