[Core] add get_opset_imports utility fxn to ModelWrapper

Author: maltanar

src/qonnx/core/modelwrapper.py

@@ -738,3 +738,7 @@ def set_tensor_sparsity(self, tensor_name, sparsity_dict):
             qa.tensor_name = tensor_name
             qa.quant_parameter_tensor_names.append(dt)
             qnt_annotations.append(qa)
+
+    def get_opset_imports(self):
+        """Returns a list of imported opsets as (domain, version) tuples."""
+        return [(opset.domain, opset.version) for opset in self._model_proto.opset_import]

tests/core/test_modelwrapper.py

@@ -68,6 +68,7 @@ def test_modelwrapper():
     inp_sparsity = {"dw": {"kernel_shape": [3, 3]}}
     model.set_tensor_sparsity(first_conv_iname, inp_sparsity)
     assert model.get_tensor_sparsity(first_conv_iname) == inp_sparsity
+    assert model.get_opset_imports() == [("", 8)]
 
 
 def test_modelwrapper_set_get_rm_initializer():