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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 _check_r(self, r):
 """the columns must orthogonal"""

        if abs(np.dot(r[:, 0], r[:, 0]) - 1) > eps or \
            abs(np.dot(r[:, 0], r[:, 0]) - 1) > eps or \
            abs(np.dot(r[:, 0], r[:, 0]) - 1) > eps or \
            np.dot(r[:, 0], r[:, 1]) > eps or \
            np.dot(r[:, 1], r[:, 2]) > eps or \
            np.dot(r[:, 2], r[:, 0]) > eps:
            raise ValueError("The rotation matrix is significantly non-orthonormal.")