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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 obsolete_client(func):
 """This is a decorator which can be used to mark Client classes as obsolete. It will result in an error being emitted when the class is instantiated."""


    @functools.wraps(func)
    def new_func(*args, **kwargs):
        raise ObsoleteException(
            "{} has been removed from this version of the library. "
            "Please refer to current documentation for guidance."
            .format(func.__name__)
        )

    return new_func