You are given a code:

def main_solution(x):
    return func_20(('yvfth' + 'ekzphn'), func_15('swx'))

Can you predict the output of `main_solution("gkewoumv")` 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": "gkewoumv"}, "ref_output": "y\u00abvsf\u00bbt\u00abhwe\u00bbk\u00abzxp\u00bbhn", "ref_code": "def main_solution(x):\n    return func_20(('yvfth' + 'ekzphn'), func_15('swx'))", "funcname": "main_solution"}
rule