Python SQLite: database is locked

I'm presuming you are actually using sqlite3 even though your code says otherwise. Here are some things to check:

1. That you don't have a hung process sitting on the file (unix: $ fuser cache.db should say nothing)
2. There isn't a cache.db-journal file in the directory with cache.db; this would indicate a crashed session that hasn't been cleaned up properly.
3. Ask the database shell to check itself: $ sqlite3 cache.db "pragma integrity_check;"
4. Backup the database $ sqlite3 cache.db ".backup cache.db.bak"
5. Remove cache.db as you probably have nothing in it (if you are just learning) and try your code again
6. See if the backup works $ sqlite3 cache.db.bak ".schema"

Failing that, read Things That Can Go Wrong and How to Corrupt Your Database Files

Set the timeout parameter in your connect call, as in:

connection = sqlite.connect('cache.db', timeout=10)