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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 deprecated(message=""):
 """ This is a decorator which can be used to mark functions as deprecated. It will result in a warning being emitted when the function is used first time and filter is set for show DeprecationWarning. """

    def decorator_wrapper(func):
        """
        Generate decorator wrapper function
        :param func: function to be decorated
        :return: wrapper
        """
        @functools.wraps(func)
        def function_wrapper(*args, **kwargs):
            """
            Wrapper which recognize deprecated line from source code
            :param args: args for actual function
            :param kwargs: kwargs for actual functions
            :return: something that actual function might returns
            """
            current_call_source = '|'.join(traceback.format_stack(inspect.currentframe()))
            if current_call_source not in function_wrapper.last_call_source:
                warnings.warn("Function {} is now deprecated! {}".format(func.__name__, message),
                              category=DeprecationWarning, stacklevel=2)
                function_wrapper.last_call_source.add(current_call_source)

            return func(*args, **kwargs)

        function_wrapper.last_call_source = set()

        return function_wrapper
    return decorator_wrapper