old_contents: """Decorator utility functions."""
  from typing import Callable, TypeVar
  
  CALLABLE_T = TypeVar("CALLABLE_T", bound=Callable)  # pylint: disable=invalid-name
  
  
  class Registry(dict):
      """Registry of items."""
  
      def register(self, name: str) -> Callable[[CALLABLE_T], CALLABLE_T]:
          """Return decorator to register item with a specific name."""
  
          def decorator(func: CALLABLE_T) -> CALLABLE_T:
              """Register decorated function."""
              self[name] = func
              return func
  
          return decorator
  
new_contents: """Decorator utility functions."""
  from collections.abc import Hashable
  from typing import Callable, TypeVar
  
  CALLABLE_T = TypeVar("CALLABLE_T", bound=Callable)  # pylint: disable=invalid-name
  
  
  class Registry(dict):
      """Registry of items."""
  
      def register(self, name: Hashable) -> Callable[[CALLABLE_T], CALLABLE_T]:
          """Return decorator to register item with a specific name."""
  
          def decorator(func: CALLABLE_T) -> CALLABLE_T:
              """Register decorated function."""
              self[name] = func
              return func
  
          return decorator
  
subject: Set Registry name parameter to Hashable type (#51203)