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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_YYTfactor(self, Y):
 """ find a matrix L which satisfies LLT = YYT. Note that L may have fewer columns than Y. """

        N, D = Y.shape
        if (N>=D):
            return Y.view(np.ndarray)
        else:
            return jitchol(tdot(Y))