You are given a code:

def main_solution(x):
    return func_20(func_20('kpqoa', 'jbb'), (x + x))

Can you predict the output of `main_solution("ncx")` 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": "ncx"}, "ref_output": "knjcpxbnqcbxoa", "ref_code": "def main_solution(x):\n    return func_20(func_20('kpqoa', 'jbb'), (x + x))", "funcname": "main_solution"}
rule