You are given a code:

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

Can you predict the output of `main_solution("rvaxqfcao")` 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": "rvaxqfcao"}, "ref_output": "r|r|v|b|a|m|x|p|q|f|c|a|o", "ref_code": "def main_solution(x):\n    return func_13(func_20(x, 'rbmp'), '|')", "funcname": "main_solution"}
rule