stop using explicit ProactorEventLoop on Windows

It is now the default in Python.

artiq/frontend/artiq_master.py

@@ -3,7 +3,6 @@
 import asyncio
 import argparse
 import atexit
-import os
 import logging
 
 from sipyco.pc_rpc import Server as RPCServer
@@ -75,11 +74,7 @@ class MasterConfig:
 def main():
     args = get_argparser().parse_args()
     log_forwarder = init_log(args)
-    if os.name == "nt":
-        loop = asyncio.ProactorEventLoop()
-        asyncio.set_event_loop(loop)
-    else:
-        loop = asyncio.get_event_loop()
+    loop = asyncio.get_event_loop()
     atexit.register(loop.close)
     bind = common_args.bind_address_from_args(args)
 

artiq/test/test_scheduler.py

@@ -2,7 +2,6 @@ import unittest
 import logging
 import asyncio
 import sys
-import os
 from time import time, sleep
 
 from artiq.experiment import *
@@ -87,10 +86,7 @@ class _RIDCounter:
 
 class SchedulerCase(unittest.TestCase):
     def setUp(self):
-        if os.name == "nt":
-            self.loop = asyncio.ProactorEventLoop()
-        else:
-            self.loop = asyncio.new_event_loop()
+        self.loop = asyncio.new_event_loop()
         asyncio.set_event_loop(self.loop)
 
     def test_steps(self):

artiq/test/test_worker.py

@@ -2,7 +2,6 @@ import unittest
 import logging
 import asyncio
 import sys
-import os
 from time import sleep
 
 from artiq.experiment import *
@@ -77,10 +76,7 @@ def _run_experiment(class_name):
 
 class WorkerCase(unittest.TestCase):
     def setUp(self):
-        if os.name == "nt":
-            self.loop = asyncio.ProactorEventLoop()
-        else:
-            self.loop = asyncio.new_event_loop()
+        self.loop = asyncio.new_event_loop()
         asyncio.set_event_loop(self.loop)
 
     def test_simple_run(self):