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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def errorhandler(self, error: Union[Type[Exception], int]) -> Callable: """Add an error handler function to the Blueprint. This is designed to be used as a decorator, and has the same arguments as :meth:`~quart.Quart.errorhandler`. It applies only to errors that originate in routes in this blueprint. An example usage, .. code-block:: python blueprint = Blueprint(__name__) @blueprint.errorhandler(404) def not_found():
 """

        def decorator(func: Callable) -> Callable:
            self.register_error_handler(error, func)
            return func
        return decorator