Update additional_data_handler.py
Custom code nodes are now collected in lbmpy in a single file: https://i10git.cs.fau.de/pycodegen/lbmpy/-/blob/master/lbmpy/custom_code_nodes.py
This MR makes all lbmpy version compatible again
Custom code nodes are now collected in lbmpy in a single file: https://i10git.cs.fau.de/pycodegen/lbmpy/-/blob/master/lbmpy/custom_code_nodes.py
This MR makes all lbmpy version compatible again