You are given a code:

def main_solution(x):
    return func_15(('wqf' + x))

Can you predict the output of `main_solution("yhzhbyfdpu")` 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": "yhzhbyfdpu"}, "ref_output": "\u00abw\u00bb\u00abq\u00bb\u00abf\u00bb\u00aby\u00bb\u00abh\u00bb\u00abz\u00bb\u00abh\u00bb\u00abb\u00bb\u00aby\u00bb\u00abf\u00bb\u00abd\u00bb\u00abp\u00bb\u00abu\u00bb", "ref_code": "def main_solution(x):\n    return func_15(('wqf' + x))", "funcname": "main_solution"}
rule