You are given a code:

def main_solution(x):
    return ('mcgf' + 'bvncso')

Can you predict the output of `main_solution("kqvidnsgck")` 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": "kqvidnsgck"}, "ref_output": "mcgfbvncso", "ref_code": "def main_solution(x):\n    return ('mcgf' + 'bvncso')", "funcname": "main_solution"}
rule