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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_to_bookmark(self, bookmark_id, tags):
 """ Add tags to to a bookmark. The identified bookmark must belong to the current user. :param bookmark_id: ID of the bookmark to delete. :param tags: Comma separated tags to be applied. """

        url = self._generate_url('bookmarks/{0}/tags'.format(bookmark_id))
        params = dict(tags=tags)
        return self.post(url, params)