You are given a code:

def main_solution(x):
    return func_20(func_15('cfl'), func_20('fdqxvs', x))

Can you predict the output of `main_solution("mnvkduap")` 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": "mnvkduap"}, "ref_output": "\u00abfcm\u00bbd\u00abnfq\u00bbv\u00abxlk\u00bbvdsuap", "ref_code": "def main_solution(x):\n    return func_20(func_15('cfl'), func_20('fdqxvs', x))", "funcname": "main_solution"}
rule