You are given a code:

def main_solution(x):
    return func_20(func_15('bxzj'), ('lxsum' + 'lwbzzj'))

Can you predict the output of `main_solution("utfr")` without writing any code? Please reason and put your final answer in the following json format: {"output": <your output>}, where <your output> should be the final string.
user
{"ref_input": {"x": "utfr"}, "ref_output": "\u00ablbx\u00bbs\u00abuxm\u00bbl\u00abwzb\u00bbz\u00abzjj\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15('bxzj'), ('lxsum' + 'lwbzzj'))", "funcname": "main_solution"}
rule