Asana synchronization fails with pexpect error

[abradd]

Every time I try to connect and pull down tasks from Asana I receive the following error:

$ todo-sync org ~/tmp/asana-test/config.el asana $ASANA_TOKEN

Traceback (most recent call last):
  File "/Users/user1/anaconda3/lib/python3.6/site-packages/pexpect/expect.py", line 111, in expect_loop
    incoming = spawn.read_nonblocking(spawn.maxread, timeout)
  File "/Users/user1/anaconda3/lib/python3.6/site-packages/pexpect/pty_spawn.py", line 485, in read_nonblocking
    return super(spawn, self).read_nonblocking(size)
  File "/Users/user1/anaconda3/lib/python3.6/site-packages/pexpect/spawnbase.py", line 176, in read_nonblocking
    raise EOF('End Of File (EOF). Empty string style platform.')
pexpect.exceptions.EOF: End Of File (EOF). Empty string style platform.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Users/user1/anaconda3/bin/todo-sync", line 10, in <module>
    sys.exit(main())
  File "/Users/user1/anaconda3/lib/python3.6/site-packages/todo_sync/command_line.py", line 47, in main
    args.behind_config, args.verbose, args.dry_run) as b_source:
  File "/Users/user1/anaconda3/lib/python3.6/site-packages/todo_sync/mappers/org_to_asana.py", line 48, in behind_source
    spawn, "Lisp expression: ", None)
  File "/Users/user1/anaconda3/lib/python3.6/site-packages/pexpect/replwrap.py", line 55, in __init__
    self._expect_prompt()
  File "/Users/user1/anaconda3/lib/python3.6/site-packages/pexpect/replwrap.py", line 66, in _expect_prompt
    timeout=timeout)
  File "/Users/user1/anaconda3/lib/python3.6/site-packages/pexpect/spawnbase.py", line 418, in expect_exact
    return exp.expect_loop(timeout)
  File "/Users/user1/anaconda3/lib/python3.6/site-packages/pexpect/expect.py", line 117, in expect_loop
    return self.eof(e)
  File "/Users/user1/anaconda3/lib/python3.6/site-packages/pexpect/expect.py", line 63, in eof
    raise EOF(msg)
pexpect.exceptions.EOF: End Of File (EOF). Empty string style platform.
<pexpect.pty_spawn.spawn object at 0x100eaa898>
command: /usr/local/bin/emacs
args: [b'/usr/local/bin/emacs', b'-batch', b'-l', b'/Users/user1/tmp/asana-test/config.el', b'-l', b'ts-org-interaction.el', b'--eval=(ts-repl)']
buffer (last 100 chars): ''
before (last 100 chars): '0.50/lisp/url" "/usr/local/Cellar/emacs-plus/HEAD-d2d4916/share/emacs/27.0.50/lisp/textmodes" ...)\r\n'
after: <class 'pexpect.exceptions.EOF'>
match: None
match_index: None
exitstatus: None
flag_eof: True
pid: 83866
child_fd: 7
closed: False
timeout: 30
delimiter: <class 'pexpect.exceptions.EOF'>
logfile: None
logfile_read: None
logfile_send: None
maxread: 2000
ignorecase: False
searchwindowsize: None
delaybeforesend: 0.05
delayafterclose: 0.1
delayafterterminate: 0.1
searcher: searcher_string:
    0: 'Lisp expression: '
    1: '[PEXPECT_PROMPT+'

My org file is empty and my config file looks like:

;;; make the downloaded ts-org-interaction library available
(add-to-list load-path (expand-file-name "~/tmp/asana-test"))

;;; set Org agenda file variables
(defvar org-directory (expand-file-name "~/tmp/asana-test"))
(defvar org-agenda-files '("asana.org"))

I'm using python 3.6.8 on macos 10.13 with org-version 9.2.3.

Any idea what could be going wrong?