You are given a code:

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

Can you predict the output of `main_solution("imsvvcwx")` 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": "imsvvcwx"}, "ref_output": "i\u00ab_pm\u00bb_\u00absz_\u00bbv\u00ab_wv\u00bb_\u00abcj_\u00bbw\u00ab_jx\u00bb\u00abj\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_13(x, '_'), func_15('pzwjjj'))", "funcname": "main_solution"}
rule