diff --git a/source/python.js b/source/python.js
index 7cb730a93a..56ddf6283e 100644
--- a/source/python.js
+++ b/source/python.js
@@ -4202,11 +4202,14 @@ python.Execution = class {
             return tensor.dtype.scalar_type();
         });
         this.registerFunction('ops.prim.is_quantized', function(tensor) {
-            return tensor && tensor.__quantized__ === true;
+            return tensor.is_quantized;
         });
         this.registerFunction('ops.prim.is_cuda', function(/* tensor */) {
             return false;
         });
+        this.registerFunction('ops.prim.is_nested', function(tensor) {
+            return tensor.is_nested;
+        });
         this.registerFunction('ops.prim.unchecked_unwrap_optional', function(value) {
             return value;
         });
@@ -5209,7 +5212,12 @@ python.Execution = class {
                 }
                 throw new python.Error("Unsupported indices in layout'" + this._indices.__str__() + "'.");
             }
-
+            get is_quantized() {
+                return this.__quantized__ === true;
+            }
+            get is_nested() {
+                return this.__nested__ === true;
+            }
             size() {
                 return this._shape;
             }
diff --git a/source/pytorch.js b/source/pytorch.js
index d28a93faad..10e7f97358 100644
--- a/source/pytorch.js
+++ b/source/pytorch.js
@@ -1210,6 +1210,9 @@ pytorch.Execution = class extends python.Execution {
                 const qualified_name = this.data && this.data.__class__ && this.data.__class__.__module__ && this.data.__class__.__name__ ? this.data.__class__.__module__ + '.' + this.data.__class__.__name__ : '';
                 return execution.invoke('torch.ClassType', [ qualified_name ]);
             }
+            get qualified_name() {
+                return this._type().qualified_name();
+            }
             get code_with_constants() {
                 const const_map = {};
                 const_map.const_mapping = new Map(Object.entries(execution.builtins.CONSTANTS));
@@ -1517,6 +1520,7 @@ pytorch.jit.Execution = class extends pytorch.Execution {
                 this._kind = kind;
                 this._inputs = [];
                 this._outputs = [];
+                this._blocks = [];
             }
             kind() {
                 return this._kind;
@@ -1527,6 +1531,9 @@ pytorch.jit.Execution = class extends pytorch.Execution {
             outputs() {
                 return this._outputs;
             }
+            blocks() {
+                return this._blocks;
+            }
             addInput(value) {
                 const use = execution.invoke('torch.Use', [ this ]);
                 value._uses.push(use);
@@ -1538,6 +1545,11 @@ pytorch.jit.Execution = class extends pytorch.Execution {
                 this._outputs.push(value);
                 return value;
             }
+            addBlock() {
+                const block = execution.invoke('torch.Block' [ this._graph, this ]);
+                this._blocks.push(block);
+                return block;
+            }
         });
         this.registerType('torch.Value', class {
             constructor(node) {
@@ -2094,7 +2106,7 @@ pytorch.jit.Execution = class extends pytorch.Execution {
             if (type.startsWith('torch.')) {
                 overloads = this._types.get('aten::' + type.substring(6));
             }
-            else if (type.startsWith('ops.')) {
+            else if (type.startsWith('ops.') && !type.startsWith('ops.prim.')) {
                 const path = type.split('.');
                 if (path.length === 3) {
                     overloads = this._types.get(path[1] + '::' + path[2]);
diff --git a/test/backend.py b/test/backend.py
index d9c0ea9bcc..a27bed8178 100755
--- a/test/backend.py
+++ b/test/backend.py
@@ -35,9 +35,10 @@ def _test_onnx_iterate():
 def _test_torchscript_transformer():
     torch = __import__('torch')
     model = torch.nn.Transformer(nhead=16, num_encoder_layers=12)
-    trace = torch.jit.trace(model, (torch.rand(10, 32, 512), torch.rand(20, 32, 512)))
-    torch._C._jit_pass_inline(trace.graph) # pylint: disable=protected-access
-    netron.serve('transformer', trace)
+    module = torch.jit.trace(model, (torch.rand(10, 32, 512), torch.rand(20, 32, 512)))
+    # module = torch.jit.script(model)
+    torch._C._jit_pass_inline(module.graph) # pylint: disable=protected-access
+    netron.serve('transformer', module)
 
 def _test_torchscript_resnet34():
     torch = __import__('torch')
diff --git a/test/models.json b/test/models.json
index 79f72896af..8c7e173e1c 100644
--- a/test/models.json
+++ b/test/models.json
@@ -4985,6 +4985,13 @@
     "format":   "TorchScript v1.0",
     "link":     "https://github.com/KinglittleQ/SuperPoint_SLAM"
   },
+  {
+    "type":     "pytorch",
+    "target":   "test.8bit.pth",
+    "source":   "https://github.com/lutzroeder/netron/files/5238524/test.8bit.pth.zip[test.8bit.pth]",
+    "format":   "TorchScript v1.6",
+    "link":     "https://github.com/lutzroeder/netron/issues/546"
+  },
   {
     "type":     "pytorch",
     "target":   "traced_fft.pt",
@@ -5022,10 +5029,18 @@
   },
   {
     "type":     "pytorch",
-    "target":   "test.8bit.pth",
-    "source":   "https://github.com/lutzroeder/netron/files/5238524/test.8bit.pth.zip[test.8bit.pth]",
+    "target":   "transformer.pt",
+    "source":   "https://github.com/lutzroeder/netron/files/10271969/transformer.pt.zip[transformer.pt]",
     "format":   "TorchScript v1.6",
-    "link":     "https://github.com/lutzroeder/netron/issues/546"
+    "error":    "AssertionError: was expecting embedding dimension of 512, but got ?",
+    "link":     "https://github.com/lutzroeder/netron/issues/842"
+  },
+  {
+    "type":     "pytorch",
+    "target":   "transformer_traced.pt",
+    "source":   "https://github.com/lutzroeder/netron/files/10271968/transformer_traced.pt.zip[transformer_traced.pt]",
+    "format":   "TorchScript v1.6",
+    "link":     "https://github.com/lutzroeder/netron/issues/842"
   },
   {
     "type":     "pytorch",