You are given a code:

def main_solution(x):
    return func_20(func_5('vtec', 'ul'), func_13('tvfzyu', '-'))

Can you predict the output of `main_solution("kpvxer")` 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": "kpvxer"}, "ref_output": "utl-vvt-efc-z-y-u", "ref_code": "def main_solution(x):\n    return func_20(func_5('vtec', 'ul'), func_13('tvfzyu', '-'))", "funcname": "main_solution"}
rule