You are given a code:

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

Can you predict the output of `main_solution("vgvzig")` 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": "vgvzig"}, "ref_output": "\u00abv\u00bb\u00abg\u00bb\u00abv\u00bb\u00abz\u00bb\u00abi\u00bb\u00abg\u00bbv-g-v-z-i-g", "ref_code": "def main_solution(x):\n    return (func_15(x) + func_13(x, '-'))", "funcname": "main_solution"}
rule