You are given a code:

def main_solution(x):
    return func_20(func_15('stjqy'), func_13(x, '_'))

Can you predict the output of `main_solution("hswi")` 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": "hswi"}, "ref_output": "\u00abhs_\u00bbs\u00ab_tw\u00bb_\u00abij\u00bb\u00abq\u00bb\u00aby\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15('stjqy'), func_13(x, '_'))", "funcname": "main_solution"}
rule