You are given a code:

def main_solution(x):
    return func_13(func_20('pmqmfe', 'jspgud'), '_')

Can you predict the output of `main_solution("mqt")` 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": "mqt"}, "ref_output": "p_j_m_s_q_p_m_g_f_u_e_d", "ref_code": "def main_solution(x):\n    return func_13(func_20('pmqmfe', 'jspgud'), '_')", "funcname": "main_solution"}
rule