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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 set_option(name, value):
 """ Set package option Parameters name : str Name of the option value : object New value of the option Returns ------- old : object Old value of the option """

    d = globals()

    if name in {'get_option', 'set_option'} or name not in d:
        from ..exceptions import PlotnineError
        raise PlotnineError("Unknown option {}".format(name))

    old = d[name]
    d[name] = value
    return old