refactor: remove redundant assignment

The code adds a name that does not improve the reader's understanding.
That is usually a poor tradeoff: it adds a statement, a local variable,
and a name that the reader must mentally associate with statement.
Do not introduce a local variable solely to satisfy a line-length limit.

Author: alessio-locatelli

aiohttp_client_cache/backends/mongodb.py

@@ -72,8 +72,7 @@ async def bulk_delete(self, keys: set):
         await self.collection.delete_many(spec)
 
     async def delete(self, key: str):
-        spec = {'_id': key}
-        await self.collection.delete_one(spec)
+        await self.collection.delete_one({'_id': key})
 
     async def keys(self) -> AsyncIterable[str]:
         async for doc in self.collection.find({}, {'_id': True}):
@@ -96,8 +95,7 @@ async def values(self) -> AsyncIterable[ResponseOrKey]:
             yield doc['data']
 
     async def write(self, key: str, item: ResponseOrKey):
-        update = {'$set': {'data': item}}
-        await self.collection.update_one({'_id': key}, update, upsert=True)
+        await self.collection.update_one({'_id': key}, {'$set': {'data': item}}, upsert=True)
 
 
 class MongoDBPickleCache(MongoDBCache):