You are given a code:

def main_solution(x):
    return func_20(func_15(x), func_20('mgmyh', 'otk'))

Can you predict the output of `main_solution("mcksdwt")` 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": "mcksdwt"}, "ref_output": "\u00abmmo\u00bbg\u00abtcm\u00bbk\u00abykh\u00bb\u00abs\u00bb\u00abd\u00bb\u00abw\u00bb\u00abt\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15(x), func_20('mgmyh', 'otk'))", "funcname": "main_solution"}
rule