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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 elekta_xvi_space(shape=(512, 512, 512), **kwargs):
 """Default reconstruction space for the Elekta XVI CBCT. Parameters shape : sequence of int, optional Shape of the space, in voxels. kwargs : Keyword arguments to pass to `uniform_discr` to modify the space, e.g. use another backend. By default, the dtype is set to float32. Returns ------- elekta_xvi_space : `DiscreteLp` Examples -------- Create default space: Create sub-sampled space: See Also -------- elekta_xvi_geometry: Geometry for the Elekta XVI CBCT. elekta_xvi_fbp: Default reconstruction method for the Elekta XVI CBCT. """

    if 'dtype' not in kwargs:
        kwargs['dtype'] = 'float32'
    return odl.uniform_discr(min_pt=[-128.0, -128, -128.0],
                             max_pt=[128.0, 128.0, 128.0],
                             shape=shape,
                             **kwargs)