You are given a code:

def main_solution(x):
    return func_5(func_17('jhpvv'), 'fvdk')

Can you predict the output of `main_solution("rakkvj")` 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": "rakkvj"}, "ref_output": "fvdkvvphj", "ref_code": "def main_solution(x):\n    return func_5(func_17('jhpvv'), 'fvdk')", "funcname": "main_solution"}
rule