In systemd-233 the format of the constants file changed to use
SD_ID128_MAKE_STR macro and long lines are broken with '\'.
Doing this in sed is too anyoing — add a simple python script to
do the processing.

We get <systemd.journal.JournalHandler object at ...> in older versions,
and <JournalHandler (NOTSET)> in since Python 3.6.
https://github.com/python/cpython/commit/c0752011472790e34d171b89f4b862cc3fd8ad08

send() already does conversions in a type-specific way, and doing it
in journal handler would defeat those conversions. In particular, UUIDs
would be converted to early and have dashes.

MESSAGE_ID passing was broken before previous commit:
TypeError: send() got multiple values for keyword argument 'MESSAGE_ID'

With the previous commit it's broken differently:

______________________________ test_journalhandler_message_id_on_handler _______________________________

    def test_journalhandler_message_id_on_handler():
        record = logging.LogRecord('test-logger', logging.INFO, 'testpath', 1, 'test', None, None)
        sender = MockSender()
        handler = journal.JournalHandler(logging.INFO, sender_function=sender.send,
                                         MESSAGE_ID=TEST_MID)
        handler.emit(record)
        assert len(sender.buf) == 1
>       assert 'MESSAGE_ID=' + TEST_MID.hex in sender.buf[0]
E       assert ('MESSAGE_ID=' + '8441372f8dca4ca98694a6091fd8519f') in ['MESSAGE=test', 'MESSAGE_ID=8441372f-8dca-4ca9-8694-a6091fd8519f', 'CODE_FILE=testpath', 'CODE_LINE=1', 'name=test-logger', 'exc_info=None', ...]
E        +  where '8441372f8dca4ca98694a6091fd8519f' = UUID('8441372f-8dca-4ca9-8694-a6091fd8519f').hex

systemd/test/test_journal.py:116: AssertionError
______________________________ test_journalhandler_message_id_on_message _______________________________

    def test_journalhandler_message_id_on_message():
        record = logging.LogRecord('test-logger', logging.INFO, 'testpath', 1, 'test', None, None)
        record.__dict__['MESSAGE_ID'] = TEST_MID2
        sender = MockSender()
        handler = journal.JournalHandler(logging.INFO, sender_function=sender.send,
                                         MESSAGE_ID=TEST_MID)
        handler.emit(record)
        assert len(sender.buf) == 1
>       assert 'MESSAGE_ID=' + TEST_MID2.hex in sender.buf[0]
E       assert ('MESSAGE_ID=' + '8441370000000000000000001fd85000') in ['MESSAGE=test', 'MESSAGE_ID=84413700-0000-0000-0000-00001fd85000', 'CODE_FILE=testpath', 'CODE_LINE=1', 'name=test-logger', 'exc_info=None', ...]
E        +  where '8441370000000000000000001fd85000' = UUID('84413700-0000-0000-0000-00001fd85000').hex

systemd/test/test_journal.py:135: AssertionError
============================ 2 failed, 53 passed, 6 skipped in 0.16 seconds ============================

Removed mid variable from JournalHandler since the MESSAGE_ID is already
in the extras variable. MESSAGE_ID was being set to None, but this won't
appear in the logs.

Let's not try to make it look like a journal field. It should
be a normal parameter.

Followup for dce0a855c3281e7051b1cbe0f73386d1c90ef320.

As with other functions, the wrapper is always present, but returns
OSError: [Errno 38] Function not implemented.