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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 resolution_phantom(shape=None):
 """Resolution phantom for tomographic simulations. Returns ------- An image with the following properties: image type: gray scales shape: [1024, 1024] (if not specified by `size`) scale: [0, 1] type: float64 """

    # TODO: Store data in some ODL controlled url
    # TODO: This can be also done with ODL's ellipse_phantom
    name = 'phantom_resolution.mat'
    url = URL_CAM + name
    dct = get_data(name, subset=DATA_SUBSET, url=url)
    im = np.rot90(dct['im'], k=3)

    return convert(im, shape)