You are given a code:

def main_solution(x):
    return (('wqvs' + 'sxhvk') + func_15('nake'))

Can you predict the output of `main_solution("gpzlkdx")` 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": "gpzlkdx"}, "ref_output": "wqvssxhvk\u00abn\u00bb\u00aba\u00bb\u00abk\u00bb\u00abe\u00bb", "ref_code": "def main_solution(x):\n    return (('wqvs' + 'sxhvk') + func_15('nake'))", "funcname": "main_solution"}
rule