You are given a code:

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

Can you predict the output of `main_solution("eaaakviuop")` 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": "eaaakviuop"}, "ref_output": "fbgjtzqbe-a-a-a-k-v-i-u-o-p", "ref_code": "def main_solution(x):\n    return (('fbgj' + 'tzqb') + func_13(x, '-'))", "funcname": "main_solution"}
rule