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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 get_yield_stress(self, n):
 """ Gets the yield stress for a given direction Args: n (3x1 array-like):
 direction for which to find the yield stress """

        # TODO: root finding could be more robust
        comp = root(self.get_stability_criteria, -1, args=n)
        tens = root(self.get_stability_criteria, 1, args=n)
        return (comp.x, tens.x)