You are given a code:

def main_solution(x):
    return func_9(func_13('njvzp', '-'))

Can you predict the output of `main_solution("igdghwzny")` 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": "igdghwzny"}, "ref_output": "n-j-v-z-pp-z-v-j-n", "ref_code": "def main_solution(x):\n    return func_9(func_13('njvzp', '-'))", "funcname": "main_solution"}
rule