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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 tag_related(self, query, category=None):
 """Get related tags. Parameters: query (str):
 The tag to find the related tags for. category (str):
 If specified, show only tags of a specific category. Can be: General 0, Artist 1, Copyright 3 and Character 4. """

        params = {'query': query, 'category': category}
        return self._get('related_tag.json', params)