You are given a code:

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

Can you predict the output of `main_solution("cbaguulnsz")` 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": "cbaguulnsz"}, "ref_output": "\u00abclb\u00bba\u00abgcu\u00bbu\u00ablvn\u00bbs\u00abzic\u00bbb\u00abaig\u00bbuulnsz", "ref_code": "def main_solution(x):\n    return func_20(func_15('lcvii'), func_1(x, 2))", "funcname": "main_solution"}
rule