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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 config_value_changed(option):
 """ Determine if config value changed since last call to this function. """

    hook_data = unitdata.HookData()
    with hook_data():
        db = unitdata.kv()
        current = config(option)
        saved = db.get(option)
        db.set(option, current)
        if saved is None:
            return False
        return current != saved