Lumerical FDTD:write_sparameters_lumerical gives ValidationError

[Kricki]

Describe the bug
When executing the Lumerical FDTD example, pydantic throws a ValidationError which comes from cross_section.py.

Full error log in the attached file: 2024-09-06_gplugins_lumerical_fdtd_error.txt

To Reproduce
Follow the example from notebook in the docs.

import lumapi
session = lumapi.FDTD()
import gdsfactory as gf
from gdsfactory.generic_tech import LAYER_STACK, get_generic_pdk

import gplugins.lumerical as sim

gf.config.rich_output()
PDK = get_generic_pdk()
PDK.activate()

c = gf.components.mmi1x2()
sim.write_sparameters_lumerical(component=c, layer_stack=LAYER_STACK, run=False, session=session)

The lumapi connection is working. Executing session = lumapi.FDTD() opens the Lumerical GUI.

Versions

• Python 3.11.9
• gdsfactory 8.8.7
• gplugins 1.1.2
• Lumerical 2024 R1.2