You are given a code:

def main_solution(x):
    return ('mvoica' + 'rfezm')

Can you predict the output of `main_solution("jok")` 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": "jok"}, "ref_output": "mvoicarfezm", "ref_code": "def main_solution(x):\n    return ('mvoica' + 'rfezm')", "funcname": "main_solution"}
rule