bpo-32066: Support pathlib.Path in create_unix_connection; sock arg should be optional (#4447)

diff --git a/Lib/asyncio/events.py b/Lib/asyncio/events.py
index f2f2e28..e59d3d2 100644
--- a/Lib/asyncio/events.py
+++ b/Lib/asyncio/events.py
@@ -362,12 +362,12 @@
         """
         raise NotImplementedError
 
-    def create_unix_connection(self, protocol_factory, path, *,
+    def create_unix_connection(self, protocol_factory, path=None, *,
                                ssl=None, sock=None,
                                server_hostname=None):
         raise NotImplementedError
 
-    def create_unix_server(self, protocol_factory, path, *,
+    def create_unix_server(self, protocol_factory, path=None, *,
                            sock=None, backlog=100, ssl=None):
         """A coroutine which creates a UNIX Domain Socket server.
 
diff --git a/Lib/asyncio/unix_events.py b/Lib/asyncio/unix_events.py
index bf682a1..be98f33 100644
--- a/Lib/asyncio/unix_events.py
+++ b/Lib/asyncio/unix_events.py
@@ -212,7 +212,7 @@
         self.call_soon_threadsafe(transp._process_exited, returncode)
 
     @coroutine
-    def create_unix_connection(self, protocol_factory, path, *,
+    def create_unix_connection(self, protocol_factory, path=None, *,
                                ssl=None, sock=None,
                                server_hostname=None):
         assert server_hostname is None or isinstance(server_hostname, str)
@@ -229,6 +229,7 @@
                 raise ValueError(
                     'path and sock can not be specified at the same time')
 
+            path = _fspath(path)
             sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM, 0)
             try:
                 sock.setblocking(False)