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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 force_balanced_LP(self):
 r"""Force balanced lamination parameters The lamination parameters `\xi_{A2}` and `\xi_{A4}` are set to null to force a balanced laminate. """

        dummy, xiA1, xiA2, xiA3, xiA4 = self.xiA
        self.xiA = np.array([1, xiA1, 0, xiA3, 0], dtype=np.float64)
        self.calc_ABDE_from_lamination_parameters()