You are given a code:

def main_solution(x):
    return func_20(func_15(x), func_15('nui'))

Can you predict the output of `main_solution("xrcboctrq")` 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": "xrcboctrq"}, "ref_output": "\u00ab\u00abxn\u00bb\u00bb\u00ab\u00abru\u00bb\u00bb\u00ab\u00abci\u00bb\u00bb\u00abb\u00bb\u00abo\u00bb\u00abc\u00bb\u00abt\u00bb\u00abr\u00bb\u00abq\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15(x), func_15('nui'))", "funcname": "main_solution"}
rule