You are given a code:

def main_solution(x):
    return (func_20(x, x) + func_13('yrqgdy', '_'))

Can you predict the output of `main_solution("ksv")` 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": "ksv"}, "ref_output": "kkssvvy_r_q_g_d_y", "ref_code": "def main_solution(x):\n    return (func_20(x, x) + func_13('yrqgdy', '_'))", "funcname": "main_solution"}
rule