Method extension

source/python.js:5330–5334

(size)

                    return array;
                }
                extension(size) {
                    const code = this._view.getUint8(this.skip(1));
                    const data = this.read(size);
                    return this._ext_hook(code, data);
                }
                skip(offset) {
                    const position = this._position;
                    this._position += offset;