Problems with using pgcli

The following error occurs above the 1.0.0 version:
-> % pgcli -h localhost -p 5432 -U postgres -W
Password:
Traceback (most recent call last):
File "/usr/bin/pgcli", line 9, in
load_entry_point('pgcli==0.20.1', 'console_scripts', 'console')()
File "/usr/local/lib/python3.5/dist-packages/click/core.py", line 722, in call
return self.main(*args, **kwargs)
File "/usr/local/lib/python3.5/dist-packages/click/core.py", line 697, in main
rv = self.invoke(ctx)
File "/usr/local/lib/python3.5/dist-packages/click/core.py", line 895, in invoke
return ctx.invoke(self.callback, **ctx.params)
File "/usr/local/lib/python3.5/dist-packages/click/core.py", line 535, in invoke
return callback(*args, **kwargs)
File "/usr/share/pgcli/pgcli/main.py", line 595, in cli
pgcli.run_cli()
File "/usr/share/pgcli/pgcli/main.py", line 278, in run_cli
self.cli = self._build_cli()
File "/usr/share/pgcli/pgcli/main.py", line 408, in _build_cli
cli = CommandLineInterface(application=application)
File "/usr/local/lib/python3.5/dist-packages/prompt_toolkit/interface.py", line 67, in init
assert isinstance(eventloop, EventLoop)
AssertionError

When I install version 0.59, I can use it properly
sudo pip install prompt_toolkit==0.59
-> % pgcli -h localhost -p 5432 -U postgres -W
Password:
Version: 0.20.1
Chat: https://gitter.im/dbcli/pgcli
Mail: https://groups.google.com/forum/#!forum/pgcli
Home: http://pgcli.com
postgres>

Reproduce the pgcli command shown and start at pgcli/main.py around run_cli and _build_cli, then inspect prompt_toolkit/interface.py where the EventLoop assertion fails. Compare the compatibility expectations for prompt-toolkit versions above 1.0.0; done means pgcli starts and connects successfully without requiring prompt-toolkit 0.59.