You are given a code:

def main_solution(x):
    return func_20(func_4(x), func_15('zgjwql'))

Can you predict the output of `main_solution("fwxk")` 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": "fwxk"}, "ref_output": "f\u00abwzx\u00bbk\u00abg\u00bb\u00abj\u00bb\u00abw\u00bb\u00abq\u00bb\u00abl\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_4(x), func_15('zgjwql'))", "funcname": "main_solution"}
rule