My web is app having major issues with some queries on sqlite3 version that is running on PA. Turns out PythonAnywhere runs some ancient version of Sqlite that causes silent 500 errors on some queries.
(virtual_env) 21:45 ~/mysite $ sqlite3
SQLite version 3.8.2 2013-12-06 14:53:30
Enter ".help" for instructions
Enter SQL statements terminated with a ";"
sqlite>
2013-12-06, trully impressive.