You are given a code:

def main_solution(x):
    return func_20(func_15(x), func_1('ndcmm', 3))

Can you predict the output of `main_solution("tmvkoa")` 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": "tmvkoa"}, "ref_output": "\u00abntd\u00bbc\u00abmmm\u00bbn\u00abdvc\u00bbm\u00abmkn\u00bbd\u00abcom\u00bbm\u00aba\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15(x), func_1('ndcmm', 3))", "funcname": "main_solution"}
rule