[pysqlite] sqlite3 - implicit close() when cursor object reclaimed?

Given this method:

    def iterkeys(self):
        c = self._conn.cursor()
        c.execute("select key from dict order by key")
        return (e[0] for e in c)

where self._conn is a sqlite3 connection (I'm using the code in Python 3.0b3
at the moment), is the cursor properly closed when the returned genexp is
freed?  I saw no mention of Cursor.close in the Python 2.6 sqlite3 docs.  In
the _sqlite/cursor.c file I see that at least part of what
pysqlite_cursor_close does is executed in pysqlite_cursor_dealloc, but not
everything.  Shouldn't pysqlite_cursor_close be called from
pysqlite_cursor_dealloc?

Thx,

Skip Montanaro