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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 start(self):
 """Starts the execution of the root state. """

        # load default input data for the state
        self._root_state.input_data = self._root_state.get_default_input_values_for_state(self._root_state)
        self._root_state.output_data = self._root_state.create_output_dictionary_for_state(self._root_state)
        new_execution_history = self._add_new_execution_history()
        new_execution_history.push_state_machine_start_history_item(self, run_id_generator())
        self._root_state.start(new_execution_history)