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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 destroy(self):
 """ Destroys the clipboard by relieving all model references. """

        self.destroy_all_models_in_dict(self.model_copies)
        self.model_copies = None
        self.copy_parent_state_id = None
        self.outcome_id_mapping_dict = None
        self.port_id_mapping_dict = None
        self.state_id_mapping_dict = None