You are given a code:

def main_solution(x):
    return (func_15('ktb') + func_13('dnqtno', '-'))

Can you predict the output of `main_solution("sso")` 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": "sso"}, "ref_output": "\u00abk\u00bb\u00abt\u00bb\u00abb\u00bbd-n-q-t-n-o", "ref_code": "def main_solution(x):\n    return (func_15('ktb') + func_13('dnqtno', '-'))", "funcname": "main_solution"}
rule