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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 makecontinuum(cube, **kwargs):
 """Make a continuum array. Args: cube (decode.cube):
 Decode cube which will be averaged over channels. kwargs (optional):
 Other arguments. inchs (list):
 Included channel kidids. exchs (list):
 Excluded channel kidids. Returns: decode cube (decode.cube):
 Decode cube (2d). """

    ### pick up kwargs
    inchs = kwargs.pop('inchs', None)
    exchs = kwargs.pop('exchs', None)

    if (inchs is not None) or (exchs is not None):
        raise KeyError('Inchs and exchs are no longer supported. Use weight instead.')

    # if inchs is not None:
    #     logger.info('inchs')
    #     logger.info('{}'.format(inchs))
    #     subcube = cube[:, :, inchs]
    # else:
    #     mask = np.full(len(cube.ch), True)
    #     if exchs is not None:
    #         logger.info('exchs')
    #         logger.info('{}'.format(exchs))
    #         mask[exchs] = False
    #     subcube = cube[:, :, mask]

    if weight is None:
        weight = 1.
    # else:
        # cont = (subcube * (1 / subcube.noise**2)).sum(dim='ch') / (1 / subcube.noise**2).sum(dim='ch')
        # cont = cont.expand_dims(dim='ch', axis=2)
    cont = (cube * (1 / weight**2)).sum(dim='ch') / (1 / weight**2).sum(dim='ch')

    ### define coordinates
    xcoords      = {'x': cube.x.values}
    ycoords      = {'y': cube.y.values}
    chcoords     = {'masterid': np.array([0]), # np.array([int(subcube.masterid.mean(dim='ch'))]),
                    'kidid': np.array([0]), # np.array([int(subcube.kidid.mean(dim='ch'))]),
                    'kidfq': np.array([0]), # np.array([float(subcube.kidfq.mean(dim='ch'))]),
                    'kidtp': np.array([1])} # np.array([1])}
    scalarcoords = {'coordsys': cube.coordsys.values, 'datatype': cube.datatype.values,
                    'xref': cube.xref.values, 'yref': cube.yref.values}

    return dc.cube(cont.values, xcoords=xcoords, ycoords=ycoords, chcoords=chcoords,
                    scalarcoords=scalarcoords)