You are given a code:

def main_solution(x):
    return func_20(func_20('iyc', 'nvfs'), func_15('grvts'))

Can you predict the output of `main_solution("cmmnhiez")` 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": "cmmnhiez"}, "ref_output": "i\u00abngy\u00bbv\u00abcrf\u00bbs\u00abv\u00bb\u00abt\u00bb\u00abs\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_20('iyc', 'nvfs'), func_15('grvts'))", "funcname": "main_solution"}
rule