You are given a code:

def main_solution(x):
    return func_20(func_15(x), func_1('tbyel', 2))

Can you predict the output of `main_solution("tritule")` 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": "tritule"}, "ref_output": "\u00abttb\u00bby\u00aberl\u00bbt\u00abbiy\u00bbe\u00ablt\u00bb\u00abu\u00bb\u00abl\u00bb\u00abe\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15(x), func_1('tbyel', 2))", "funcname": "main_solution"}
rule