code: def elekta_xvi_space(shape=(512, 512, 512), **kwargs):
      
      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)
docs: 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:
  
      >>> from odl.contrib import tomo
      >>> space = tomo.elekta_xvi_space()
  
      Create sub-sampled space:
  
      >>> space = tomo.elekta_xvi_space(shape=(100, 100, 100))
  
      See Also
      --------
      elekta_xvi_geometry: Geometry for the Elekta XVI CBCT.
      elekta_xvi_fbp: Default reconstruction method for the Elekta XVI CBCT.