How to use the specutils.spectra.SpectralCoord function in specutils

else:
        new_mask = None

    if spectrum.uncertainty is not None:
        new_uncertainty = np.delete(spectrum.uncertainty, excise_indices)
    else:
        new_uncertainty = None

    # Return a new object with the regions excised.
    return Spectrum1D(flux=new_flux,
                      spectral_axis=new_spectral_axis,
                      uncertainty=new_uncertainty,
                      mask=new_mask,
                      wcs=spectrum.wcs,
                      velocity_convention=spectrum.velocity_convention,
                      rest_value=spectrum.rest_value if not isinstance(new_spectral_axis, SpectralCoord) else None,
                      radial_velocity=spectrum.radial_velocity if not isinstance(new_spectral_axis, SpectralCoord) else None)

def from_tree(cls, node, ctx):
        if isinstance(node, SpectralCoord):
            return node

        unit = UnitType.from_tree(node['unit'], ctx)
        value = node['value']
        if isinstance(value, NDArrayType):
            value = value._make_array()
        return SpectralCoord(value, unit=unit)

modified_flux[s:e+1] = np.linspace(flux[s], flux[e], modified_flux[s:e+1].size)

        # Add the uncertainty of the two linear interpolation endpoints in
        # quadrature and apply to the excised region.
        if new_uncertainty is not None:
            new_uncertainty[s:e] = np.sqrt(spectrum.uncertainty[s]**2 + spectrum.uncertainty[e]**2)

    # Return a new object with the regions excised.
    return Spectrum1D(flux=modified_flux,
                      spectral_axis=spectral_axis,
                      uncertainty=new_uncertainty,
                      wcs=spectrum.wcs,
                      mask=spectrum.mask,
                      velocity_convention=spectrum.velocity_convention,
                      rest_value=spectrum.rest_value if not isinstance(spectral_axis, SpectralCoord) else None,
                      radial_velocity=spectrum.radial_velocity if not isinstance(spectral_axis, SpectralCoord) else None)

def to_tree(cls, spec_coord, ctx):
        node = {}
        if isinstance(spec_coord, SpectralCoord):
            node['value'] = custom_tree_to_tagged_tree(spec_coord.value, ctx)
            node['unit'] = custom_tree_to_tagged_tree(spec_coord.unit, ctx)
            return node
        raise TypeError(f"'{spec_coord}' is not a valid SpectralCoord")

    @classmethod
    def assert_equal(cls, old, new):
        """
        Equality test used in ASDF unit tests
        """
        assert len(old) == len(new)
        for x, y in zip(old, new):
            Spectrum1DType.assert_equal(x, y)


class SpectralCoordType(SpecutilsType):
    """
    ASDF tag implementation used to serialize/derialize SpectralCoord objects
    """
    name = 'spectra/spectral_coord'
    types = [SpectralCoord]
    version = '1.0.0'

    @classmethod
    def to_tree(cls, spec_coord, ctx):
        node = {}
        if isinstance(spec_coord, SpectralCoord):
            node['value'] = custom_tree_to_tagged_tree(spec_coord.value, ctx)
            node['unit'] = custom_tree_to_tagged_tree(spec_coord.unit, ctx)
            return node
        raise TypeError(f"'{spec_coord}' is not a valid SpectralCoord")

    @classmethod
    def from_tree(cls, node, ctx):
        if isinstance(node, SpectralCoord):
            return node