You are given a code:

def main_solution(x):
    return func_20(func_15('qvmz'), (x + 'psjeuk'))

Can you predict the output of `main_solution("llgtfhefog")` 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": "llgtfhefog"}, "ref_output": "\u00ablql\u00bbg\u00abtvf\u00bbh\u00abemf\u00bbo\u00abgzp\u00bbsjeuk", "ref_code": "def main_solution(x):\n    return func_20(func_15('qvmz'), (x + 'psjeuk'))", "funcname": "main_solution"}
rule