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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 add_tags(self, md5, tags):
 """Add tags to this sample"""

        if not tags: return
        tag_set = set(self.get_tags(md5)) if self.get_tags(md5) else set()
        if isinstance(tags, str):
            tags = [tags]
        for tag in tags:
            tag_set.add(tag)
        self.data_store.store_work_results({'tags': list(tag_set)}, 'tags', md5)