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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 converged_ionic(self):
 """ Checks that ionic step convergence has been reached, i.e. that vasp exited before reaching the max ionic steps for a relaxation run """

        nsw = self.parameters.get("NSW", 0)
        return nsw <= 1 or len(self.ionic_steps) < nsw