You are given a code:

def main_solution(x):
    return func_20(func_20(x, 'itxoj'), func_15(x))

Can you predict the output of `main_solution("becmtbywhk")` 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": "becmtbywhk"}, "ref_output": "b\u00abibe\u00bbt\u00abcex\u00bbm\u00aboct\u00bbj\u00abbmy\u00bbw\u00abhtk\u00bb\u00abb\u00bb\u00aby\u00bb\u00abw\u00bb\u00abh\u00bb\u00abk\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_20(x, 'itxoj'), func_15(x))", "funcname": "main_solution"}
rule