You are given a code:

def main_solution(x):
    return func_5(func_17(x), 'otkz')

Can you predict the output of `main_solution("fjygbkctv")` 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": "fjygbkctv"}, "ref_output": "otkzvtckbgyjf", "ref_code": "def main_solution(x):\n    return func_5(func_17(x), 'otkz')", "funcname": "main_solution"}
rule