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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 get(self, slug):
 """Get list of mappings. Url parameters: - from: filter "mappings from" - to: filter "mappings to" - page - per_page - match_type: s=substring, e=exact, sw=startswith - sortby: 'from' or 'to' """

        kb = api.get_kb_by_slug(slug)

        # check if is accessible from api
        check_knowledge_access(kb)

        parser = reqparse.RequestParser()
        parser.add_argument(
            'from', type=str,
            help="Return only entries where 'from' matches this.")
        parser.add_argument(
            'to', type=str,
            help="Return only entries where 'to' matches this.")
        parser.add_argument('page', type=int,
                            help="Require a specific page")
        parser.add_argument('per_page', type=int,
                            help="Set how much result per page")
        parser.add_argument('match_type', type=str,
                            help="s=substring, e=exact, sw=startswith")
        parser.add_argument('sortby', type=str,
                            help="the sorting criteria ('from' or 'to')")
        args = parser.parse_args()
        return KnwKBMappingsResource \
            .search_mappings(kb, args['from'], args['to'],
                             args['match_type'], args['sortby'],
                             args['page'], args['per_page'])