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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 lotus_root_data():
 """Tomographic X-ray data of a lotus root. Notes ----- See the article `Tomographic X-ray data of a lotus root filled with attenuating objects`_ for further information. See Also -------- lotus_root_geometry References .. _Tomographic X-ray data of a lotus root filled with attenuating objects: https://arxiv.org/abs/1609.07299 """

    # TODO: Store data in some ODL controlled url
    url = 'http://www.fips.fi/dataset/CT_Lotus_v1/sinogram.mat'
    dct = get_data('lotus_root.mat', subset=DATA_SUBSET, url=url)

    # Change axes to match ODL definitions
    data = np.swapaxes(dct['sinogram'], 0, 1)[:, :]
    data = data.astype('float')

    return data