How to simulate user input on an interpreter using a Python's pty module

pty.py

import os, sys, subprocess, pty, select, re

BUFSIZ = 1024
MAGIC = '\004\004' # ctrl-D x2
escape = re.compile(r'(\x9B|\x1B\[)[0-?]*[ -\/]*[@-~]')

data = '\n'.join([
    '1 + 1',
    '2000',
    '(function() {})',
    '"yee"',
]) + '\n' + MAGIC

master, slave = pty.openpty()
p = subprocess.Popen('node',
                     stdin=slave,
                     stdout=slave,
                     stderr=subprocess.STDOUT)

while p.poll() is None:
    r, w, _ = select.select([master], [master], [], 0)
    if r:
        sys.stdout.write(escape.sub('', os.read(master, BUFSIZ)))
    if w and data:
        data = data[os.write(master, data):]