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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 scoped_instance(cls, optionable):
 """Returns an instance of this subsystem for exclusive use by the given `optionable`. :API: public :param optionable: An optionable type or instance to scope this subsystem under. :type: :class:`pants.option.optionable.Optionable` :returns: The scoped subsystem instance. :rtype: :class:`pants.subsystem.subsystem.Subsystem` """

    if not isinstance(optionable, Optionable) and not issubclass(optionable, Optionable):
      raise TypeError('Can only scope an instance against an Optionable, given {} of type {}.'
                      .format(optionable, type(optionable)))
    return cls._instance_for_scope(cls.subscope(optionable.options_scope))