You are given a code:

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

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