diff --git a/include/core/graph_handler.h b/include/core/graph_handler.h
index 0a54ab41..53fd9f32 100644
--- a/include/core/graph_handler.h
+++ b/include/core/graph_handler.h
@@ -51,6 +51,7 @@ class GraphHandlerObj {
     Tensor tanh(Tensor x, Tensor y);
     Tensor softmax(Tensor x, Tensor y);
     Tensor abs(Tensor x, Tensor y);
+    Tensor identity(Tensor x, Tensor y);
 };
 
 } // namespace infini
diff --git a/pyinfinitensor/src/pyinfinitensor/onnx.py b/pyinfinitensor/src/pyinfinitensor/onnx.py
index 38277614..709529de 100644
--- a/pyinfinitensor/src/pyinfinitensor/onnx.py
+++ b/pyinfinitensor/src/pyinfinitensor/onnx.py
@@ -58,6 +58,38 @@ def from_onnx(model: onnx.ModelProto):
                 tensors[node.input[1]],
                 tensors.get(node.output[0], None),
             )
+        elif node.op_type == "Relu":
+            tensors[node.output[0]] = handler.relu(
+                tensors[node.input[0]],
+                tensors.get(node.output[0], None),
+            )
+        elif node.op_type == "Sigmoid":
+            tensors[node.output[0]] = handler.sigmoid(
+                tensors[node.input[0]],
+                tensors.get(node.output[0], None),
+            )
+        elif node.op_type == "Tanh":
+            tensors[node.output[0]] = handler.tanh(
+                tensors[node.input[0]],
+                tensors.get(node.output[0], None),
+            )
+        elif node.op_type == "Softmax":
+            tensors[node.output[0]] = handler.softmax(
+                tensors[node.input[0]],
+                tensors.get(node.output[0], None),
+            )
+        elif node.op_type == "Abs":
+            tensors[node.output[0]] = handler.abs(
+                tensors[node.input[0]],
+                tensors.get(node.output[0], None),
+            )
+        elif node.op_type == "Identity":
+            tensors[node.output[0]] = handler.identity(
+                tensors[node.input[0]],
+                tensors.get(node.output[0], None),
+            )
+        else:
+            raise Exception('Unsupported operator "{}"'.format(node.op_type))
 
 
 def parse_onnx(model: onnx.ModelProto):
diff --git a/pyinfinitensor/tests/test_onnx.py b/pyinfinitensor/tests/test_onnx.py
index 9ba1d802..c3b23c34 100644
--- a/pyinfinitensor/tests/test_onnx.py
+++ b/pyinfinitensor/tests/test_onnx.py
@@ -135,7 +135,7 @@ class TestStringMethods(unittest.TestCase):
         x = make_tensor_value_info("x", TensorProto.FLOAT, [1, 2, 3])
         a = make_tensor_value_info("a", TensorProto.FLOAT, [1, 3, 4])
         b = make_tensor_value_info("b", TensorProto.FLOAT, [1, 2, 4])
-        y = make_tensor_value_info("b", TensorProto.FLOAT, [1, 2, 4])
+        y = make_tensor_value_info("y", TensorProto.FLOAT, [1, 2, 4])
         matmul = make_node("MatMul", ["x", "a"], ["xa"], name="matmul")
         add = make_node("Add", ["xa", "b"], ["y"], name="add")
         graph = make_graph([matmul, add], "lr", [x, a, b], [y])
diff --git a/src/core/graph_handler.cc b/src/core/graph_handler.cc
index 17fa2d18..a32ecd64 100644
--- a/src/core/graph_handler.cc
+++ b/src/core/graph_handler.cc
@@ -1,6 +1,7 @@
 #include "core/graph_handler.h"
 #include "operators/element_wise.h"
 #include "operators/matmul.h"
+#include "operators/reshape.h"
 #include "operators/unary.h"
 
 namespace infini {
@@ -58,6 +59,8 @@ DEFINE_UNARY_METHOD(sigmoid, Sigmoid)
 DEFINE_UNARY_METHOD(tanh, Tanh)
 DEFINE_UNARY_METHOD(softmax, Softmax)
 DEFINE_UNARY_METHOD(abs, Abs)
+// see operators/reshape.h
+DEFINE_UNARY_METHOD(identity, Identity)
 
 static DataType dtype_repr_convert(int dtype) {
     switch ((OnnxDType)dtype) {
diff --git a/src/ffi/ffi_infinitensor.cc b/src/ffi/ffi_infinitensor.cc
index e61e422f..2de5bc1b 100644
--- a/src/ffi/ffi_infinitensor.cc
+++ b/src/ffi/ffi_infinitensor.cc
@@ -22,6 +22,8 @@ void register_operator_timer(py::module &m) {
 }
 
 void init_graph_builder(py::module &m) {
+    using Handler = GraphHandlerObj;
+
     m.def("cpu_runtime", &CpuRuntimeObj::getInstance);
     py::class_<RuntimeObj, std::shared_ptr<RuntimeObj>>(m, "RuntimeObj");
     py::class_<CpuRuntimeObj, std::shared_ptr<CpuRuntimeObj>, RuntimeObj>(
@@ -36,40 +38,35 @@ void init_graph_builder(py::module &m) {
         .value("Tanh", ActType::Tanh)
         .export_values();
     py::class_<GraphHandler>(m, "GraphHandler");
-    py::class_<GraphHandlerObj>(m, "GraphHandlerObj")
+    py::class_<Handler>(m, "GraphHandlerObj")
         .def(py::init<Runtime>())
-        .def("tensor", py::overload_cast<Shape, int>(&GraphHandlerObj::tensor),
-             policy::reference_internal)
+        .def("tensor", py::overload_cast<Shape, int>(&Handler::tensor),
+             policy::move)
         .def("matmul",
              py::overload_cast<Tensor, Tensor, Tensor, bool, bool, Tensor,
-                               ActType>(&GraphHandlerObj::matmul),
+                               ActType>(&Handler::matmul),
              policy::move)
-        .def("add",
-             py::overload_cast<Tensor, Tensor, Tensor>(&GraphHandlerObj::add),
+        .def("add", py::overload_cast<Tensor, Tensor, Tensor>(&Handler::add),
              policy::move)
-        .def("sub",
-             py::overload_cast<Tensor, Tensor, Tensor>(&GraphHandlerObj::sub),
+        .def("sub", py::overload_cast<Tensor, Tensor, Tensor>(&Handler::sub),
              policy::move)
-        .def("mul",
-             py::overload_cast<Tensor, Tensor, Tensor>(&GraphHandlerObj::mul),
+        .def("mul", py::overload_cast<Tensor, Tensor, Tensor>(&Handler::mul),
              policy::move)
-        .def("div",
-             py::overload_cast<Tensor, Tensor, Tensor>(&GraphHandlerObj::div),
+        .def("div", py::overload_cast<Tensor, Tensor, Tensor>(&Handler::div),
              policy::move)
-        .def("pow",
-             py::overload_cast<Tensor, Tensor, Tensor>(&GraphHandlerObj::pow),
+        .def("pow", py::overload_cast<Tensor, Tensor, Tensor>(&Handler::pow),
              policy::move)
-        .def("relu", py::overload_cast<Tensor, Tensor>(&GraphHandlerObj::relu),
+        .def("relu", py::overload_cast<Tensor, Tensor>(&Handler::relu),
              policy::move)
-        .def("sigmoid",
-             py::overload_cast<Tensor, Tensor>(&GraphHandlerObj::sigmoid),
+        .def("sigmoid", py::overload_cast<Tensor, Tensor>(&Handler::sigmoid),
              policy::move)
-        .def("tanh", py::overload_cast<Tensor, Tensor>(&GraphHandlerObj::tanh),
-             policy::reference_internal)
-        .def("softmax",
-             py::overload_cast<Tensor, Tensor>(&GraphHandlerObj::softmax),
+        .def("tanh", py::overload_cast<Tensor, Tensor>(&Handler::tanh),
              policy::move)
-        .def("abs", py::overload_cast<Tensor, Tensor>(&GraphHandlerObj::abs),
+        .def("softmax", py::overload_cast<Tensor, Tensor>(&Handler::softmax),
+             policy::move)
+        .def("abs", py::overload_cast<Tensor, Tensor>(&Handler::abs),
+             policy::move)
+        .def("identity", py::overload_cast<Tensor, Tensor>(&Handler::identity),
              policy::move);
 }