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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, code_or_exception):
 """ Register a function to handle errors by code or exception class. A decorator that is used to register a function given an error code. Example:: @app.errorhandler(404) def page_not_found(error):
 return 'This page does not exist', 404 You can also register handlers for arbitrary exceptions:: @app.errorhandler(DatabaseError) def special_exception_handler(error):
 return 'Database connection failed', 500 :param code_or_exception: the code as integer for the handler, or an arbitrary exception """

        def decorator(fn):
            self._defer(lambda app: app.register_error_handler(code_or_exception, fn))
            return fn
        return decorator