You are given a code:

def main_solution(x):
    return func_20(func_15('wlkhua'), func_1(x, 4))

Can you predict the output of `main_solution("kdniio")` 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": "kdniio"}, "ref_output": "\u00abkwd\u00bbn\u00abili\u00bbo\u00abkkd\u00bbn\u00abihi\u00bbo\u00abkud\u00bbn\u00abiai\u00bbokdniio", "ref_code": "def main_solution(x):\n    return func_20(func_15('wlkhua'), func_1(x, 4))", "funcname": "main_solution"}
rule