You are given a code:

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

Can you predict the output of `main_solution("mucvrhaxk")` 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": "mucvrhaxk"}, "ref_output": "\u00abfmy\u00bbg\u00abmuu\u00bbc\u00abvcr\u00bbh\u00abavx\u00bbk\u00abr\u00bb\u00abh\u00bb\u00aba\u00bb\u00abx\u00bb\u00abk\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15(x), func_5(x, 'fyg'))", "funcname": "main_solution"}
rule