[Core, Util] distinguish preferred onnx opset from qonnx opset

Author: maltanar

src/qonnx/core/modelwrapper.py

@@ -743,7 +743,7 @@ def get_opset_imports(self):
         """Returns a list of imported opsets as a {domain, version} dictionary."""
         return {opset.domain: opset.version for opset in self._model_proto.opset_import}
 
-    def get_customop_wrapper(self, node, fallback_customop_version=1):
+    def get_customop_wrapper(self, node, fallback_customop_version=util.get_preferred_qonnx_opset()):
         """Return CustomOp instance for given node, respecting the
         imported opset version in the model protobuf. If the node's domain
         is not found in the model's opset imports, fallback_customop_version

src/qonnx/util/basic.py

@@ -51,11 +51,19 @@ def get_preferred_onnx_opset():
     return 11
 
 
+def get_preferred_qonnx_opset():
+    "Return preferred ONNX opset version for QONNX"
+    return 1
+
+
 def qonnx_make_model(graph_proto, **kwargs):
     "Wrapper around ONNX make_model with preferred qonnx opset version"
     opset_imports = kwargs.pop("opset_imports", None)
     if opset_imports is None:
-        opset_imports = [make_opsetid("", get_preferred_onnx_opset())]
+        opset_imports = [
+            make_opsetid("", get_preferred_onnx_opset()),
+            make_opsetid("qonnx.custom_op.general", get_preferred_qonnx_opset()),
+        ]
         kwargs["opset_imports"] = opset_imports
     else:
         kwargs["opset_imports"] = opset_imports