modify the code format

Author: bestcondition

tornado/platform/asyncio.py

@@ -495,7 +495,7 @@ async def thread_manager_anext() -> None:
         # starting.
         self._real_loop.call_soon(
             lambda: self._real_loop.create_task(thread_manager_anext()),
-            context=self._main_thread_ctx
+            context=self._main_thread_ctx,
         )
 
         self._readers: Dict[_FileDescriptorLike, Callable] = {}
@@ -623,8 +623,7 @@ def _run_select(self) -> None:
 
             try:
                 self._real_loop.call_soon_threadsafe(
-                    self._handle_select, rs, ws,
-                    context=self._main_thread_ctx
+                    self._handle_select, rs, ws, context=self._main_thread_ctx
                 )
             except RuntimeError:
                 # "Event loop is closed". Swallow the exception for

tornado/test/asyncio_test.py

@@ -271,9 +271,9 @@ def test_tornado_accessor(self):
 
 
 class SelectorThreadContextvarsTest(AsyncHTTPTestCase):
-    ctx_value = 'foo'
-    test_endpoint = '/'
-    tornado_test_ctx = contextvars.ContextVar('tornado_test_ctx', default='default')
+    ctx_value = "foo"
+    test_endpoint = "/"
+    tornado_test_ctx = contextvars.ContextVar("tornado_test_ctx", default="default")
     tornado_test_ctx.set(ctx_value)
 
     def get_app(self) -> Application: