Fix TypeError for openpmd plugin

Author: mafshari64

lib/python/picongpu/picmi/diagnostics/checkpoint.py

@@ -108,6 +108,7 @@ def get_as_pypicongpu(
         pypicongpu_by_picmi_species: Dict,
         time_step_size: float,
         num_steps: int,
+        simulation_box=None,  # Added to match OpenPMD signature, not used
     ) -> PyPIConGPUCheckpoint:
         self.check()
 

lib/python/picongpu/picmi/diagnostics/energy_histogram.py

@@ -79,6 +79,7 @@ def get_as_pypicongpu(
         dict_species_picmi_to_pypicongpu: dict[PICMISpecies, PyPIConGPUSpecies],
         time_step_size,
         num_steps,
+        simulation_box=None,  # Added to match OpenPMD signature, not used
     ) -> PyPIConGPUEnergyHistogram:
         self.check()
 

lib/python/picongpu/picmi/diagnostics/macro_particle_count.py

@@ -49,6 +49,7 @@ def get_as_pypicongpu(
         dict_species_picmi_to_pypicongpu: dict[PICMISpecies, PyPIConGPUSpecies],
         time_step_size,
         num_steps,
+        simulation_box=None,  # Added to match OpenPMD signature, not used
     ) -> PyPIConGPUMacroParticleCount:
         self.check()
 

lib/python/picongpu/picmi/diagnostics/png.py

@@ -189,6 +189,7 @@ def get_as_pypicongpu(
         dict_species_picmi_to_pypicongpu: dict[PICMISpecies, PyPIConGPUSpecies],
         time_step_size,
         num_steps,
+        simulation_box=None,  # Added to match OpenPMD signature, not used
     ) -> PyPIConGPUPNG:
         self.check()
 

lib/python/picongpu/pypicongpu/output/openpmd.py

@@ -80,10 +80,19 @@ def _get_serialized(self) -> typing.Dict:
         Serialize the OpenPMD object to a JSON-compatible dictionary.
         """
         self.check()
+
+        # Convert RangeSpec to string format
+        range_context = self.range._get_serialized() if self.range is not None else None
+        if range_context:
+            specs = range_context["specs"]
+            range_str = ",".join(f"{spec['start']}:{spec['stop']}" for spec in specs)
+        else:
+            range_str = None
+
         return {
             "period": self.period._get_serialized(),
             "source": [s._get_serialized() for s in self.source] if self.source is not None else None,
-            "range": self.range._get_serialized() if self.range is not None else None,
+            "range": range_str,
             "file": self.file,
             "ext": self.ext,
             "infix": self.infix,