Unable to save state including material

[lucashfrancisco]

For hybrid undulators, states cannot be saved because they include a Material object (for the poles) which cannot be serialized. This issue arose when trying to use saved states to avoid the necessity of repeating a solve() execution, as pointed out by @Gabrielrezende-asc.

from imaids.models import HybridPlanar
und = HybridPlanar()
und.save_state('saved_state.json')

Results in:

TypeError: Object of type VanadiumPermendur is not JSON serializable

[fernandohds564]

@lucashfrancisco, wouldn't it be possible to serialize them with pickle, which in the python built-in serializer?