You are given a code:

def main_solution(x):
    return func_20(func_11('jplma', 3), func_13('auljv', '-'))

Can you predict the output of `main_solution("yxxjm")` 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": "yxxjm"}, "ref_output": "mas-oup-dl-j-v", "ref_code": "def main_solution(x):\n    return func_20(func_11('jplma', 3), func_13('auljv', '-'))", "funcname": "main_solution"}
rule