Breaks on latest Python compiler

[wu4f]

For Python compiler versions after vyper==0.1.0-beta.12, attempting to do a local compile from Remix gives this error. Plug-in works fine with 0.1.0-beta.12

% vyper-serve
Listening on http://localhost:8000
127.0.0.1 - - [07/May/2020 11:59:38] "OPTIONS /compile HTTP/1.1" 200 -

Exception happened during processing of request from ('127.0.0.1', 40418)
Traceback (most recent call last):
File "/usr/lib/python3.6/socketserver.py", line 654, in process_request_thread
self.finish_request(request, client_address)
File "/usr/lib/python3.6/socketserver.py", line 364, in finish_request
self.RequestHandlerClass(request, client_address, self)
File "/usr/lib/python3.6/socketserver.py", line 724, in init
self.handle()
File "/usr/lib/python3.6/http/server.py", line 418, in handle
self.handle_one_request()
File "/usr/lib/python3.6/http/server.py", line 406, in handle_one_request
method()
File "/usr/local/home/www/html/thefengs/wuchang/courses/cs410b/cs410b-src/gbsrc/vyper/env/lib/python3.6/site-packages/vyper/cli/vyper_serve.py", line 82, in do_POST
response, status_code = self._compile(data)
File "/usr/local/home/www/html/thefengs/wuchang/courses/cs410b/cs410b-src/gbsrc/vyper/env/lib/python3.6/site-packages/vyper/cli/vyper_serve.py", line 106, in _compile
vyper.compiler.output_formats_map.keys(),
File "/usr/local/home/www/html/thefengs/wuchang/courses/cs410b/cs410b-src/gbsrc/vyper/env/lib/python3.6/site-packages/vyper/compiler.py", line 310, in compile_codes
for output_format in output_formats[contract_name]:
TypeError: 'dict_keys' object is not subscriptable