Hang without any feedback

[aes]

Running walkthrough.sh, I get this:

> ./walkthrough.sh                 
~ Asciicast recording started.
~ Hit Ctrl-D or type "exit" to finish.
2017-09-26 12:39:42,955 INFO: ShutIt modules loaded
2017-09-26 12:39:42,962 INFO: Configuration loaded

And no indication or instruction about what is supposed to happen, if I need to press any key or keys.(Ctrl-d doesn't seem to do anything) Checking in Virtualbox, I see no activity, so I Ctrl-c and get this trace:

^CTraceback (most recent call last):
  File "/home/aes/src/playpen/kthw/env/bin/shutit", line 11, in <module>
    sys.exit(main())
  File "/home/aes/src/playpen/kthw/env/lib/python3.5/site-packages/shutit.py", line 61, in main
    shutit.setup_shutit_obj()
  File "/home/aes/src/playpen/kthw/env/lib/python3.5/site-packages/shutit_class.py", line 3921, in setup_shutit_obj
    self.conn_target()
  File "/home/aes/src/playpen/kthw/env/lib/python3.5/site-packages/shutit_class.py", line 4329, in conn_target
    conn_module.build(self)
  File "/home/aes/src/playpen/kthw/env/lib/python3.5/site-packages/shutit_module.py", line 59, in wrapper
    ret = func(self, shutit)
  File "/home/aes/src/playpen/kthw/env/lib/python3.5/site-packages/shutit_setup.py", line 135, in build
    self.setup_host_child(shutit)
  File "/home/aes/src/playpen/kthw/env/lib/python3.5/site-packages/shutit_setup.py", line 49, in setup_host_child
    shutit.setup_host_child_environment()
  File "/home/aes/src/playpen/kthw/env/lib/python3.5/site-packages/shutit_class.py", line 3754, in setup_host_child_environment
    shutit_pexpect_session.setup_prompt('ORIGIN_ENV', prefix=prefix)
  File "/home/aes/src/playpen/kthw/env/lib/python3.5/site-packages/shutit_pexpect.py", line 449, in setup_prompt
    ignore_background=True))
  File "/home/aes/src/playpen/kthw/env/lib/python3.5/site-packages/shutit_pexpect.py", line 2636, in send
    expect_res = shutit.expect_allow_interrupt(self.pexpect_child, sendspec.expect, sendspec.timeout)
  File "/home/aes/src/playpen/kthw/env/lib/python3.5/site-packages/shutit_class.py", line 827, in expect_allow_interrupt
    res = shutit_pexpect_session.expect(expect, timeout=iteration_s)
  File "/home/aes/src/playpen/kthw/env/lib/python3.5/site-packages/shutit_pexpect.py", line 531, in expect
    res = self.pexpect_child.expect(expect + [pexpect.TIMEOUT] + [pexpect.EOF], timeout=timeout)
  File "/usr/lib/python3/dist-packages/pexpect/spawnbase.py", line 321, in expect
    timeout, searchwindowsize, async)
  File "/usr/lib/python3/dist-packages/pexpect/spawnbase.py", line 345, in expect_list
    return exp.expect_loop(timeout)
  File "/usr/lib/python3/dist-packages/pexpect/expect.py", line 99, in expect_loop
    incoming = spawn.read_nonblocking(spawn.maxread, timeout)
  File "/usr/lib/python3/dist-packages/pexpect/pty_spawn.py", line 452, in read_nonblocking
    r, w, e = select_ignore_interrupts([self.child_fd], [], [], timeout)
  File "/usr/lib/python3/dist-packages/pexpect/utils.py", line 138, in select_ignore_interrupts
    return select.select(iwtd, owtd, ewtd, timeout)
KeyboardInterrupt

Trying to redo it with python 2.7 fails because 2.7 isn't supported by asciinema