[ONNX] Fix node attributes when namespace is aten (pytorch#84211)

When `g.at` is used, the previous clean up in pytorch#83136 mistakenly removed the behavior that sets `aten=True` in `_add_attribute`. This PR brings the behavior back.
Pull Request resolved: pytorch#84211
Approved by: https://github.com/thiagocrepaldi, https://github.com/BowenBao

torch/onnx/_patch_torch.py

@@ -101,17 +101,18 @@ def _aten_op(g: _C.Graph, operator: str, *args, overload_name: str = "", **kwarg
 
 
 @_beartype.beartype
-def _block_op(b: _C.Block, opname: str, *args: _C.Value, **kwargs):
+def _block_op(block: _C.Block, opname: str, *args: _C.Value, **kwargs):
     if "::" in opname:
-        aten = False
-        ns_opname = opname
+        namespace, op = opname.split("::")
     else:
-        aten = kwargs.pop("aten", False)
-        ns = "aten" if aten else "onnx"
-        ns_opname = ns + "::" + opname
-    n = b.addNode(ns_opname, args)
+        namespace = "onnx"
+        op = opname
+
+    n = block.addNode(f"{namespace}::{op}", args)
+    aten = namespace == "aten"
+    skip_attrs = {"inplace", "aten"}
     for k, v in sorted(kwargs.items()):
-        if k == "inplace":
+        if k in skip_attrs:
             continue
         _add_attribute(n, k, v, aten=aten)
     outputs = tuple(n.outputs())
@@ -135,10 +136,11 @@ def _new_node(
     Returns:
         The new node.
     """
-    aten = kwargs.pop("aten", False)
+    aten = namespace == "aten"
     node = g.create(f"{namespace}::{op}", args, outputs)
+    skip_attrs = {"inplace", "aten"}
     for k, v in sorted(kwargs.items()):
-        if k == "inplace":
+        if k in skip_attrs:
             continue
         _add_attribute(node, k, v, aten=aten)
     return node
@@ -175,7 +177,7 @@ def _add_attribute(node: _C.Node, key: str, value: Any, aten: bool):
     if m is None:
         raise ValueError(
             f"Invalid attribute specifier '{key}' names "
-            " must be suffixed with type, e.g. 'dim_i' or 'dims_i'"
+            "must be suffixed with type, e.g. 'dim_i' or 'dims_i'"
         )
     name, kind = m.group(1), m.group(2)
     if _is_onnx_list(value):