You are given a code:

def main_solution(x):
    return func_20(func_19(x, 1), func_15('wxxc'))

Can you predict the output of `main_solution("dkmbtdtk")` 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": "dkmbtdtk"}, "ref_output": "k\u00abmwb\u00bbt\u00abdxt\u00bbk\u00abdx\u00bb\u00abc\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_19(x, 1), func_15('wxxc'))", "funcname": "main_solution"}
rule