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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 generate_sample_set(self, tags=None):
 """Generate a sample_set that maches the tags or all if tags are not specified. Args: tags: Match samples against this tag list (or all if not specified) Returns: The sample_set of those samples matching the tags """

        if isinstance(tags, str):
            tags = [tags]
        md5_list = self.data_store.tag_match(tags)
        return self.store_sample_set(md5_list)