You are given a code:

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

Can you predict the output of `main_solution("yzobtzvjnl")` 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": "yzobtzvjnl"}, "ref_output": "\u00abv\u00bb\u00abg\u00bb\u00abb\u00bb\u00abs\u00bb\u00abn\u00bb\u00abs\u00bby-z-o-b-t-z-v-j-n-l", "ref_code": "def main_solution(x):\n    return (func_15('vgbsns') + func_13(x, '-'))", "funcname": "main_solution"}
rule