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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 schedule(self, when=None, action=None, **kwargs):
 """ Schedule this item to be published. :param when: Date/time when this item should go live. None means now. """

        action = '_publish'
        super(BaseVersionedModel, self).schedule(when=when, action=action,
                                                 **kwargs)