You are given a code:

def main_solution(x):
    return (func_4(x) + func_15('wlcra'))

Can you predict the output of `main_solution("bghf")` 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": "bghf"}, "ref_output": "bghf\u00abw\u00bb\u00abl\u00bb\u00abc\u00bb\u00abr\u00bb\u00aba\u00bb", "ref_code": "def main_solution(x):\n    return (func_4(x) + func_15('wlcra'))", "funcname": "main_solution"}
rule