Decorator is using in class,but not working

[Yoriz]

Your decorator extract_function_name does not need to be in class ScientificCalculator
and it needs to return internal_method, at the moment it defaults to returning None.

def extract_function_name(func):
    def internal_method(*args,**kwargs):
        print('the method called is:',func.__name__)
        returned_value = func(*args,**kwargs)
        print('the method execution is complete')
        return returned_value
    return internal_method