You are given a code:

def main_solution(x):
    return func_20(func_15('fbfme'), func_9('xdclj'))

Can you predict the output of `main_solution("cpkj")` 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": "cpkj"}, "ref_output": "\u00abxfd\u00bbc\u00ablbj\u00bbj\u00ablfc\u00bbd\u00abxm\u00bb\u00abe\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15('fbfme'), func_9('xdclj'))", "funcname": "main_solution"}
rule