You are given a code:

def main_solution(x):
    return func_20(func_13('xddngm', '_'), func_15('hqi'))

Can you predict the output of `main_solution("cuf")` 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": "cuf"}, "ref_output": "x\u00ab_hd\u00bb_\u00abdq_\u00bbn\u00ab_ig\u00bb_m", "ref_code": "def main_solution(x):\n    return func_20(func_13('xddngm', '_'), func_15('hqi'))", "funcname": "main_solution"}
rule