You are given a code:

def main_solution(x):
    return ('gcue' + 'mlpn')

Can you predict the output of `main_solution("txmvrfdum")` 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": "txmvrfdum"}, "ref_output": "gcuemlpn", "ref_code": "def main_solution(x):\n    return ('gcue' + 'mlpn')", "funcname": "main_solution"}
rule