You are given a code:

def main_solution(x):
    return func_20(func_5(x, 'otfs'), func_15('alvx'))

Can you predict the output of `main_solution("vxofuk")` 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": "vxofuk"}, "ref_output": "o\u00abtaf\u00bbs\u00abvlx\u00bbo\u00abfvu\u00bbk\u00abx\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_5(x, 'otfs'), func_15('alvx'))", "funcname": "main_solution"}
rule