You are given a code:

def main_solution(x):
    return func_20(('vxqa' + 'gqhcnn'), func_15('crwda'))

Can you predict the output of `main_solution("btnooobh")` 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": "btnooobh"}, "ref_output": "v\u00abxcq\u00bba\u00abgrq\u00bbh\u00abcwn\u00bbn\u00abd\u00bb\u00aba\u00bb", "ref_code": "def main_solution(x):\n    return func_20(('vxqa' + 'gqhcnn'), func_15('crwda'))", "funcname": "main_solution"}
rule