You are given a code:

def main_solution(x):
    return func_20(func_15(x), func_13('icefbh', '-'))

Can you predict the output of `main_solution("vihtul")` 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": "vihtul"}, "ref_output": "\u00abiv-\u00bbc\u00ab-ie\u00bb-\u00abfh-\u00bbb\u00ab-th\u00bb\u00abu\u00bb\u00abl\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15(x), func_13('icefbh', '-'))", "funcname": "main_solution"}
rule