``np.linalg`` functions return namedtuples
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``np.linalg`` functions that return tuples now return namedtuples. These
functions are ``eig()``, ``eigh()``, ``qr()``, ``slogdet()``, and ``svd()``.
The return type is unchanged in instances where these functions return
non-tuples with certain keyword arguments (like ``svd(compute_uv=False)``).