You are given a code:

def main_solution(x):
    return func_20('ibe', 'wfaotc')

Can you predict the output of `main_solution("rtnthgkaxd")` 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": "rtnthgkaxd"}, "ref_output": "iwbfeaotc", "ref_code": "def main_solution(x):\n    return func_20('ibe', 'wfaotc')", "funcname": "main_solution"}
rule