You are given a code:

def main_solution(x):
    return func_20(func_20(x, 'hpvcxb'), func_15('pngl'))

Can you predict the output of `main_solution("uwpgpxs")` 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": "uwpgpxs"}, "ref_output": "u\u00abhpw\u00bbp\u00abpnv\u00bbg\u00abcgp\u00bbx\u00abxlb\u00bbs", "ref_code": "def main_solution(x):\n    return func_20(func_20(x, 'hpvcxb'), func_15('pngl'))", "funcname": "main_solution"}
rule