You are given a code:

def main_solution(x):
    return func_20(func_15('cxpn'), (x).swapcase())

Can you predict the output of `main_solution("gcgbckjqi")` 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": "gcgbckjqi"}, "ref_output": "\u00abGcC\u00bbG\u00abBxC\u00bbK\u00abJpQ\u00bbI\u00abn\u00bb", "ref_code": "def main_solution(x):\n    return func_20(func_15('cxpn'), (x).swapcase())", "funcname": "main_solution"}
rule