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import { createServer } from "http";
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export default async function getPort(): Promise<number> {
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  return new Promise((resolve, reject) => {
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    const server = createServer();
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    server.listen(0, () => {
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      const address = server.address();
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      if (typeof address === "object" && address !== null) {
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        const port = address.port;
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        server.close(() => resolve(port));
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      } else {
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        reject(new Error("Failed to get port"));
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      }
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    });
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    server.on("error", reject);
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  });
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}
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export async function getPorts(n: number): Promise<number[]> {
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  const v: any[] = [];
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  for (let i = 0; i < n; i++) {
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    v.push(getPort());
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  }
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  return Promise.all(v);
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}
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