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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 mri_knee_data_8_channel():
 """Raw data for 8 channel MRI of a knee. This is an SE measurement of the knee of a healthy volunteer. The data has been rescaled so that the reconstruction fits approximately in [0, 1]. See the data source with DOI `10.5281/zenodo.800529`_ or the `project webpage`_ for further information. See Also -------- mri_knee_inverse_8_channel References .. _10.5281/zenodo.800529: https://zenodo.org/record/800529 .. _project webpage: http://imsc.uni-graz.at/mobis/internal/\ platform_aktuell.html """

    # TODO: Store data in some ODL controlled url
    url = 'https://zenodo.org/record/800529/files/3_rawdata_knee_8ch.mat'
    dct = get_data('3_rawdata_knee_8ch.mat', subset=DATA_SUBSET, url=url)

    # Change axes to match ODL definitions
    data = flip(np.swapaxes(dct['rawdata'], 0, -1) * 9e3, 2)

    return data