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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 _update_best_params_link(self):
 """ Updates the params.best link to the latest best parameter file. """

        best_params_path = self.best_params_fname
        actual_best_params_fname = C.PARAMS_NAME % self.state.best_checkpoint
        if os.path.lexists(best_params_path):
            os.remove(best_params_path)
        os.symlink(actual_best_params_fname, best_params_path)