Fix code style: reduce try-except body length (WPS229)

Author: proboscis

returns/primitives/reawaitable.py

@@ -4,11 +4,12 @@
 
 # Try to use anyio.Lock, fall back to asyncio.Lock
 try:
-    import anyio
-    Lock = anyio.Lock
+    import anyio  # noqa: WPS433
 except ImportError:
-    import asyncio
+    import asyncio  # noqa: WPS433
     Lock = asyncio.Lock
+else:
+    Lock = anyio.Lock
 
 _ValueType = TypeVar('_ValueType')
 _AwaitableT = TypeVar('_AwaitableT', bound=Awaitable)