I am using Python's DiskCache and the memoize decorator to cache function calls to a database of static data.

```py

from diskcache import Cache
cache = Cache("database_cache)

@cache.memoize()
def fetch_document(row_id: int, user: str, password: str):
    ...

```

I don't want the user and password be part of the cache key.

How can I exclude parameters from the key generation?