You are given a code:

def main_solution(x):
    return ('pzmu' + 'slj')

Can you predict the output of `main_solution("kzkrsv")` 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": "kzkrsv"}, "ref_output": "pzmuslj", "ref_code": "def main_solution(x):\n    return ('pzmu' + 'slj')", "funcname": "main_solution"}
rule