You are given a code:

def main_solution(x):
    return func_5('mfibfm', 'zihg')

Can you predict the output of `main_solution("rcag")` 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": "rcag"}, "ref_output": "zihgmfibfm", "ref_code": "def main_solution(x):\n    return func_5('mfibfm', 'zihg')", "funcname": "main_solution"}
rule