Update src/power_grid_model_io/data_stores/json_file_store.py

Co-authored-by: Nitish Bharambe <[email protected]>
Signed-off-by: Santiago Figueroa Manrique <[email protected]>

Author: figueroa1395

src/power_grid_model_io/data_stores/json_file_store.py

@@ -105,5 +105,5 @@ def _validate(self, data: StructuredData) -> None:
             if len(type_names) == 1:
                 type_str = type_names.pop()
             else:
-                type_str = type_str = " | ".join(type_names)
+                type_str = " | ".join(type_names)
             raise TypeError(f"Invalid data type for {type(self).__name__}: List[{type_str}]")