Обзор

import jwt  # pip install pyjwt[crypto]

token = jwt.encode(
    {"aud": "ai-seven:api"},
    open("private.pem").read(),
    algorithm="RS256",
    headers={"kid": "<ваш kid>"},
)

import jwt from "jsonwebtoken";
import { readFileSync } from "fs";

const token = jwt.sign({ aud: "ai-seven:api" }, readFileSync("private.pem"), {
  algorithm: "RS256",
  keyid: "<ваш kid>",
});

<?php
use Firebase\JWT\JWT;

$token = JWT::encode(
    ['aud' => 'ai-seven:api'],
    file_get_contents('private.pem'),
    'RS256',
    '<ваш kid>'
);