code: def test_mixed_namespace_schema_registration_code_valid(self) -> None:
      (
          aten_registrations,
          custom_registrations,
      ) = get_native_function_schema_registrations(
          native_functions=[
              DEFAULT_NATIVE_FUNCTION,
              self.custom_native_function,
          ],
          schema_selector=self.selector,
      )
      self.assertEqual(
          aten_registrations, ['m.def("func() -> bool", {});\n']
      )
      self.assertEqual(
          custom_registrations,
          """
  TORCH_LIBRARY(custom, m) {
    m.def("func() -> bool", {});
  
  };""",
      )
  
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 5 for calling the TestGenSchemaRegistration obj's underlying member method code with example usage: obj.test_mixed_namespace_schema_registration_code_valid() without return types