You are given a code:

def main_solution(x):
    return func_20(func_15('vrydsk'), func_5(x, 'hgz'))

Can you predict the output of `main_solution("fstsj")` 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": "fstsj"}, "ref_output": "\u00abhvg\u00bbz\u00abfrs\u00bbt\u00absyj\u00bb\u00abd\u00bb\u00abs\u00bb\u00abk\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15('vrydsk'), func_5(x, 'hgz'))", "funcname": "main_solution"}
rule