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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 axis_transform(pca_axes):
 """ Creates an affine transformation matrix to rotate data in PCA axes into Cartesian plane """

    from_ = N.identity(3)
    to_ = pca_axes

    # Find inverse transform for forward transform
    # y = M x -> M = y (x)^(-1)
    # We don't need to do least-squares since
    # there is a simple transformation
    trans_matrix = N.linalg.lstsq(from_,to_)[0]
    return trans_matrix