You are given a code:

def main_solution(x):
    return func_20(('fmg' + x), func_15(x))

Can you predict the output of `main_solution("silfiahlmu")` 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": "silfiahlmu"}, "ref_output": "f\u00abmsg\u00bbs\u00abiil\u00bbf\u00abila\u00bbh\u00ablfm\u00bbu\u00abi\u00bb\u00aba\u00bb\u00abh\u00bb\u00abl\u00bb\u00abm\u00bb\u00abu\u00bb", "ref_code": "def main_solution(x):\n    return func_20(('fmg' + x), func_15(x))", "funcname": "main_solution"}
rule