Read the code carefully

import os, shutil, tempfile

with tempfile.TemporaryDirectory() as root:
    src = os.path.join(root, "src")
    os.makedirs(src)
    with open(os.path.join(src, "a.txt"), "w") as f: f.write("hello")
    with open(os.path.join(src, "b.txt"), "w") as f: f.write("world")
    dst = os.path.join(root, "dst")
    shutil.copytree(src, dst)
    print(sorted(os.listdir(dst)))

What will the program print? Write here: