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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 noninjectable(*args):
 """Mark some parameters as not injectable. This serves as documentation for people reading the code and will prevent Injector from ever attempting to provide the parameters. For example: :func:`noninjectable` decorations can be stacked on top of each other and the order in which a function is decorated with :func:`inject` and :func:`noninjectable` doesn't matter. """


    def decorator(function):
        argspec = inspect.getfullargspec(inspect.unwrap(function))
        for arg in args:
            if arg not in argspec.args and arg not in argspec.kwonlyargs:
                raise UnknownArgument('Unable to mark unknown argument %s ' 'as non-injectable.' % arg)

        existing = getattr(function, '__noninjectables__', set())
        merged = existing | set(args)
        function.__noninjectables__ = merged
        return function

    return decorator