You are given a code:

def main_solution(x):
    return func_20(func_1('fldhfz', 4), func_15(x))

Can you predict the output of `main_solution("iberguihj")` 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": "iberguihj"}, "ref_output": "f\u00ablid\u00bbh\u00abfbz\u00bbf\u00abled\u00bbh\u00abfrz\u00bbf\u00ablgd\u00bbh\u00abfuz\u00bbf\u00ablid\u00bbh\u00abfhz\u00bb\u00abj\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_1('fldhfz', 4), func_15(x))", "funcname": "main_solution"}
rule