You are given a code:

def main_solution(x):
    return func_20('stimlf', 'okvdaa')

Can you predict the output of `main_solution("fbgzrk")` 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": "fbgzrk"}, "ref_output": "sotkivmdlafa", "ref_code": "def main_solution(x):\n    return func_20('stimlf', 'okvdaa')", "funcname": "main_solution"}
rule