You are given a code:

def main_solution(x):
    return func_20(func_20('fyh', x), func_15('vlozev'))

Can you predict the output of `main_solution("gkf")` 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": "gkf"}, "ref_output": "f\u00abgvy\u00bbk\u00abhlf\u00bb\u00abo\u00bb\u00abz\u00bb\u00abe\u00bb\u00abv\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_20('fyh', x), func_15('vlozev'))", "funcname": "main_solution"}
rule