Use check_same_thread=False by default for history sqlite db (#13886) I had run into the following exception while trying to use IPython in a thread: ``` Traceback (most recent call last): File "/usr/local/lib/python3.11/dist-packages/IPython/core/interactiveshell.py", line 3745, in atexit_operations self._atexit_once() File "/usr/local/lib/python3.11/dist-packages/IPython/core/interactiveshell.py", line 3728, in _atexit_once self.history_manager.end_session() File "/usr/local/lib/python3.11/dist-packages/IPython/core/history.py", line 576, in end_session self.writeout_cache() File "/usr/local/lib/python3.11/dist-packages/decorator.py", line 232, in fun return caller(func, *(extras + args), **kw) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/usr/local/lib/python3.11/dist-packages/IPython/core/history.py", line 60, in only_when_enabled return f(self, *a, **kw) ^^^^^^^^^^^^^^^^^ File "/usr/local/lib/python3.11/dist-packages/IPython/core/history.py", line 831, in writeout_cache self._writeout_input_cache(conn) File "/usr/local/lib/python3.11/dist-packages/IPython/core/history.py", line 812, in _writeout_input_cache with conn: sqlite3.ProgrammingError: SQLite objects created in a thread can only be used in that same thread. The object was created in thread id 139673788811008 and this is thread id 139673823184704. ``` And discovered that an issue (#680) has been open for it since 2011. Back in [2012](https://github.com/ipython/ipython/issues/680#issuecomment-3444922), it seems like the only reason not to fix it was that the parameter `check_same_thread` was not documented, but now [it is](https://docs.python.org/3.11/library/sqlite3.html#sqlite3.connect), and it has been at least since [3.6](https://docs.python.org/3.6/library/sqlite3.html#sqlite3.connect). Note that according to the docs: > check_same_thread ([bool](https://docs.python.org/3/library/functions.html#bool)) – If True (default), only the creating thread may use the connection. If False, the connection may be shared across multiple threads; if so, write operations should be serialized by the user to avoid data corruption. But I don't think this is an issue here. The operations should be synchronized by the user only *on the same connection object*, and if I'm not mistaken, if two instances of IPython were started in separate threads, they'd each have their own history manager with its own connection. The exception above (and the one in the related issue) is raised from `atexit`, when the main thread is running finalizations registered by other threads. At that point, the operations are serial anyway because they are executed in a single thread.