You are given a code:

def main_solution(x):
    return ('uul' + 'lpv')

Can you predict the output of `main_solution("ujmema")` 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": "ujmema"}, "ref_output": "uullpv", "ref_code": "def main_solution(x):\n    return ('uul' + 'lpv')", "funcname": "main_solution"}
rule