You are given a code:

def main_solution(x):
    return func_20(func_15(x), func_15('fvoelz'))

Can you predict the output of `main_solution("negjtycuzn")` 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": "negjtycuzn"}, "ref_output": "\u00ab\u00abnf\u00bb\u00bb\u00ab\u00abev\u00bb\u00bb\u00ab\u00abgo\u00bb\u00bb\u00ab\u00abje\u00bb\u00bb\u00ab\u00abtl\u00bb\u00bb\u00ab\u00abyz\u00bb\u00bb\u00abc\u00bb\u00abu\u00bb\u00abz\u00bb\u00abn\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15(x), func_15('fvoelz'))", "funcname": "main_solution"}
rule