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* ``log_to_seq`` now returns the SeqLogHandler to enable forced flushing of log records to Seq.
* Change ``auto_flush_timeout`` to a ``float`` representing seconds (instead of milliseconds).
* Update ``testharness.py`` to actually log to Seq.
You can override the server URL and API key using the ``SEQ_SERVER_URL`` and ``SEQ_API_KEY`` environment variables.
* Update usage information in documentation.
* Python 3 only for now (sorry, but logging in Python 2 doesn't have all the required extensibility points). If the need to support Python 2 becomes great enough then I'll try to find a way.