try_delete: key name fixed

redis_cache/backends/base.py

@@ -509,7 +509,8 @@ class BaseRedisCache(BaseCache):
     @get_client(write=True)
     def try_delete(self, client, key):
         """Remove a key from the cache if not locked."""
-        lock = cache.lock(key, timeout=5)
+        lock_key = "__lock__" + key
+        lock = cache.lock(lock_key, timeout=5)
         acquired = lock.acquire(blocking=False)
         if acquired:
             try: