My code:

const DiscordMusicBot = require("./structures/DiscordMusicBot");
const client = new DiscordMusicBot();

client.build();

module.exports = client; 

When I start the bot it gives me this error::

client.build();
       ^

TypeError: client.build is not a function
    at Object.<anonymous> (C:\Users\notli\Desktop\oxiria-music\index.js:4:8)
    at Module._compile (node:internal/modules/cjs/loader:1103:14)
    at Object.Module._extensions..js (node:internal/modules/cjs/loader:1157:10)
    at Module.load (node:internal/modules/cjs/loader:981:32)
    at Function.Module._load (node:internal/modules/cjs/loader:822:12)
    at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:77:12)
    at node:internal/main/run_main_module:17:47

Can someone help me?