You are given a code:

def main_solution(x):
    return (func_13('pfrkep', '-') + func_15(x))

Can you predict the output of `main_solution("cucgsx")` 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": "cucgsx"}, "ref_output": "p-f-r-k-e-p\u00abc\u00bb\u00abu\u00bb\u00abc\u00bb\u00abg\u00bb\u00abs\u00bb\u00abx\u00bb", "ref_code": "def main_solution(x):\n    return (func_13('pfrkep', '-') + func_15(x))", "funcname": "main_solution"}
rule