You are given a code:

def main_solution(x):
    return func_9('xemex')

Can you predict the output of `main_solution("tplbjtpzs")` 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": "tplbjtpzs"}, "ref_output": "xemexxemex", "ref_code": "def main_solution(x):\n    return func_9('xemex')", "funcname": "main_solution"}
rule