You are given a code:

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

Can you predict the output of `main_solution("hdttyf")` 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": "hdttyf"}, "ref_output": "h\u00abdmt\u00bbt\u00abytf\u00bbh\u00abdit\u00bbt\u00abyvf\u00bb\u00abl\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_1(x, 2), func_15('mtivl'))", "funcname": "main_solution"}
rule