code: def register_extension_dtype(
      cls: type_t[ExtensionDtypeT],
  ) -> type_t[ExtensionDtypeT]:
      """
      Register an ExtensionType with pandas as class decorator.
  
      This enables operations like ``.astype(name)`` for the name
      of the ExtensionDtype.
  
      Returns
      -------
      callable
          A class decorator.
  
      Examples
      --------
      >>> from pandas.api.extensions import register_extension_dtype, ExtensionDtype
      >>> @register_extension_dtype
      ... class MyExtensionDtype(ExtensionDtype):
      ...     name = "myextension"
      """
      _registry.register(cls)
      return cls
  
imports: from __future__ import annotations
  from typing import TYPE_CHECKING, Any, TypeVar, cast, overload
  import numpy
  from pandas._libs import missing
  from pandas._libs.hashtable import object_hash
  from pandas._libs.properties import cache_readonly
  from pandas.errors import AbstractMethodError
  from pandas.core.dtypes.generic import ABCDataFrame, ABCIndex, ABCSeries
label_desc: Use image node_id 1 for calling a global function with example usage: register_extension_dtype(cls) and returns: cls