You are given a code:

def main_solution(x):
    return func_20(func_15('louy'), ('bteb' + 'lnt'))

Can you predict the output of `main_solution("nkirmnksa")` 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": "nkirmnksa"}, "ref_output": "\u00abblt\u00bbe\u00abbol\u00bbn\u00abtu\u00bb\u00aby\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15('louy'), ('bteb' + 'lnt'))", "funcname": "main_solution"}
rule