You are given a code:

def main_solution(x):
    return func_20(func_15(x), ('zkap' + x))

Can you predict the output of `main_solution("eqilvsp")` 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": "eqilvsp"}, "ref_output": "\u00abzek\u00bba\u00abpqe\u00bbq\u00abiil\u00bbv\u00abslp\u00bb\u00abv\u00bb\u00abs\u00bb\u00abp\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15(x), ('zkap' + x))", "funcname": "main_solution"}
rule