diff --git a/janus/__init__.py b/janus/__init__.py
index 3126bde..ad3d204 100644
--- a/janus/__init__.py
+++ b/janus/__init__.py
@@ -509,23 +509,19 @@ async def put(self, item: T) -> None:
         parent = self._parent
         parent._check_closing()
         async with parent._async_not_full:
-            parent._sync_mutex.acquire()
-            locked = True
-            parent._get_loop()  # check the event loop
-            try:
+            with parent._sync_mutex:
+                parent._get_loop()  # check the event loop
                 if parent._maxsize > 0:
                     do_wait = True
                     while do_wait:
                         do_wait = parent._qsize() >= parent._maxsize
                         if do_wait:
                             parent._async_not_full_waiting += 1
-                            locked = False
                             parent._sync_mutex.release()
                             try:
                                 await parent._async_not_full.wait()
                             finally:
                                 parent._sync_mutex.acquire()
-                                locked = True
                                 parent._async_not_full_waiting -= 1
 
                 parent._put_internal(item)
@@ -533,9 +529,6 @@ async def put(self, item: T) -> None:
                     parent._async_not_empty.notify()
                 if parent._sync_not_empty_waiting:
                     parent._sync_not_empty.notify()
-            finally:
-                if locked:
-                    parent._sync_mutex.release()
 
     def put_nowait(self, item: T) -> None:
         """Put an item into the queue without blocking.
@@ -566,23 +559,19 @@ async def get(self) -> T:
         parent = self._parent
         parent._check_closing()
         async with parent._async_not_empty:
-            parent._sync_mutex.acquire()
-            locked = True
-            parent._get_loop()  # check the event loop
-            try:
+            with parent._sync_mutex:
+                parent._get_loop()  # check the event loop
                 do_wait = True
                 while do_wait:
                     do_wait = parent._qsize() == 0
 
                     if do_wait:
                         parent._async_not_empty_waiting += 1
-                        locked = False
                         parent._sync_mutex.release()
                         try:
                             await parent._async_not_empty.wait()
                         finally:
                             parent._sync_mutex.acquire()
-                            locked = True
                             parent._async_not_empty_waiting -= 1
 
                 item = parent._get()
@@ -591,9 +580,6 @@ async def get(self) -> T:
                 if parent._sync_not_full_waiting:
                     parent._sync_not_full.notify()
                 return item
-            finally:
-                if locked:
-                    parent._sync_mutex.release()
 
     def get_nowait(self) -> T:
         """Remove and return an item from the queue.
@@ -655,9 +641,8 @@ async def join(self) -> None:
         parent = self._parent
         parent._check_closing()
         async with parent._async_tasks_done:
-            parent._sync_mutex.acquire()
-            parent._get_loop()  # check the event loop
-            try:
+            with parent._sync_mutex:
+                parent._get_loop()  # check the event loop
                 while parent._unfinished_tasks:
                     parent._async_tasks_done_waiting += 1
                     parent._sync_mutex.release()
@@ -667,8 +652,6 @@ async def join(self) -> None:
                         parent._sync_mutex.acquire()
                         parent._async_tasks_done_waiting -= 1
                     parent._check_closing()
-            finally:
-                parent._sync_mutex.release()
 
 
 class PriorityQueue(Queue[T]):