You are given a code:

def main_solution(x):
    return func_20(func_15('wwf'), func_20(x, 'nvc'))

Can you predict the output of `main_solution("uxnroowj")` 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": "uxnroowj"}, "ref_output": "\u00abuwn\u00bbx\u00abvwn\u00bbc\u00abrfo\u00bbowj", "ref_code": "def main_solution(x):\n    return func_20(func_15('wwf'), func_20(x, 'nvc'))", "funcname": "main_solution"}
rule