You are given a code:

def main_solution(x):
    return func_20(func_11('oczr', 4), func_15('suojb'))

Can you predict the output of `main_solution("bkf")` 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": "bkf"}, "ref_output": "s\u00abgsd\u00bbv\u00abu\u00bb\u00abo\u00bb\u00abj\u00bb\u00abb\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_11('oczr', 4), func_15('suojb'))", "funcname": "main_solution"}
rule