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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 state_dict(self) -> Dict[str, Any]: """ A ``Trainer`` can use this to serialize the state of the metric tracker. """

        return {
                "best_so_far": self._best_so_far,
                "patience": self._patience,
                "epochs_with_no_improvement": self._epochs_with_no_improvement,
                "is_best_so_far": self._is_best_so_far,
                "should_decrease": self._should_decrease,
                "best_epoch_metrics": self.best_epoch_metrics,
                "epoch_number": self._epoch_number,
                "best_epoch": self.best_epoch
        }