You are given a code:

def main_solution(x):
    return func_4(func_19('dkt', 3))

Can you predict the output of `main_solution("qnavnlvi")` 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": "qnavnlvi"}, "ref_output": "dkt", "ref_code": "def main_solution(x):\n    return func_4(func_19('dkt', 3))", "funcname": "main_solution"}
rule