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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 remove_state(self, state_id, recursive=True, force=False, destroy=True):
 """Remove a state from the container state. :param state_id: the id of the state to remove :param recursive: a flag to indicate a recursive disassembling of all substates :param force: a flag to indicate forcefully deletion of all states (important for the decider state in the barrier concurrency state) :param destroy: a flag which indicates if the state should not only be disconnected from the state but also destroyed, including all its state elements :raises exceptions.AttributeError: if state.state_id does not """

        if state_id not in self.states:
            raise AttributeError("State_id %s does not exist" % state_id)

        if state_id == self.start_state_id:
            self.set_start_state(None)

        # first delete all transitions and data_flows, which are connected to the state to be deleted
        keys_to_delete = []
        for key, transition in self.transitions.items():
            if transition.from_state == state_id or transition.to_state == state_id:
                keys_to_delete.append(key)
        for key in keys_to_delete:
            self.remove_transition(key, True)

        keys_to_delete = []
        for key, data_flow in self.data_flows.items():
            if data_flow.from_state == state_id or data_flow.to_state == state_id:
                keys_to_delete.append(key)
        for key in keys_to_delete:
            self.remove_data_flow(key)

        if recursive and not destroy:
            raise AttributeError("The recursive flag requires the destroy flag to be set, too.")

        if destroy:
            # Recursively delete all transitions, data flows and states within the state to be deleted
            self.states[state_id].destroy(recursive)

        # final delete the state it self
        self.states[state_id].parent = None
        return self.states.pop(state_id)