You are given a code:

def main_solution(x):
    return func_20(func_15(x), ('nfjhc' + x))

Can you predict the output of `main_solution("epvjq")` 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": "epvjq"}, "ref_output": "\u00abnef\u00bbj\u00abhpc\u00bbe\u00abpvv\u00bbj\u00abqj\u00bb\u00abq\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15(x), ('nfjhc' + x))", "funcname": "main_solution"}
rule