You are given a code:

def main_solution(x):
    return func_20(func_15(x), func_13('stkzg', '|'))

Can you predict the output of `main_solution("clpavuywb")` 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": "clpavuywb"}, "ref_output": "\u00absc|\u00bbt\u00ab|lk\u00bb|\u00abzp|\u00bbg\u00aba\u00bb\u00abv\u00bb\u00abu\u00bb\u00aby\u00bb\u00abw\u00bb\u00abb\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15(x), func_13('stkzg', '|'))", "funcname": "main_solution"}
rule