You are given a code:

def main_solution(x):
    return func_20(func_4('ayujl'), func_17('zqtvq'))

Can you predict the output of `main_solution("yaeqsfm")` 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": "yaeqsfm"}, "ref_output": "aqyvutjqlz", "ref_code": "def main_solution(x):\n    return func_20(func_4('ayujl'), func_17('zqtvq'))", "funcname": "main_solution"}
rule