You are given a code:

def main_solution(x):
    return (func_15(x) + func_13('ngpqt', '_'))

Can you predict the output of `main_solution("grxmhitkp")` 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": "grxmhitkp"}, "ref_output": "\u00abg\u00bb\u00abr\u00bb\u00abx\u00bb\u00abm\u00bb\u00abh\u00bb\u00abi\u00bb\u00abt\u00bb\u00abk\u00bb\u00abp\u00bbn_g_p_q_t", "ref_code": "def main_solution(x):\n    return (func_15(x) + func_13('ngpqt', '_'))", "funcname": "main_solution"}
rule