code: def test_op_with_cpp_sig_generates_static_dispatch(self) -> None:
      sig_group = CppSignatureGroup.from_native_function(
          self.one_return_func,
          method=False,
          fallback_binding=self.one_return_func.manual_cpp_binding,
      )
      # cpp signature puts out at the front
      with native_function_manager(self.one_return_func):
          out = static_dispatch(
              sig=sig_group.signature,
              f=self.one_return_func,
              backend_indices=self.indices,
          )
      self.assertEqual(
          out,
          "return at::compositeexplicitautograd::op_out(out, self);",
      )
  
imports: import dataclasses
  import typing
  import unittest
  from collections import defaultdict
  from typing import Dict, List
  import torchgen.model
  import yaml
  from tools.autograd import gen_autograd_functions, load_derivatives
  from torchgen import dest
  from torchgen.api.types import CppSignatureGroup, DispatcherSignature
  from torchgen.context import native_function_manager
  from torchgen.gen import get_native_function_declarations, get_native_function_schema_registrations, LineLoader, static_dispatch
  from torchgen.model import BackendIndex, BackendMetadata, DispatchKey, Location, NativeFunction, OperatorName
  from torchgen.native_function_generation import add_generated_native_functions
  from torchgen.selective_build.selector import SelectiveBuilder
label_desc: Use image node_id 3 for calling the TestStaticDispatchGeneratrion obj's underlying member method code with example usage: obj.test_op_with_cpp_sig_generates_static_dispatch() without return types