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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 addItemTag(self, item, tag):
 """ Add a tag to an individal item. tag string must be in form "user/-/label/[tag]" """

        if self.inItemTagTransaction:
            # XXX: what if item's parent is not a feed?
            if not tag in self.addTagBacklog:
                self.addTagBacklog[tag] = []                
            self.addTagBacklog[tag].append({'i': item.id, 's': item.parent.id})
            return "OK"
        else:
            return self._modifyItemTag(item.id, 'a', tag)