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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 find_tags(self, tag_name, **attribute_filter):
 """ Return a list of all the matched tags in all available xml :param str tag: specify the tag name """

        all_tags = [
            self.find_tags_from_xml(
                i, tag_name, **attribute_filter
            )
            for i in self.xml
        ]
        return [tag for tag_list in all_tags for tag in tag_list]