You are given a code:

def main_solution(x):
    return func_13(func_5(x, 'qd'), '_')

Can you predict the output of `main_solution("grdenwzlwy")` 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": "grdenwzlwy"}, "ref_output": "q_d_g_r_d_e_n_w_z_l_w_y", "ref_code": "def main_solution(x):\n    return func_13(func_5(x, 'qd'), '_')", "funcname": "main_solution"}
rule