PTS 9: Args packing after non-default arguments

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Some days ago I was writing a Python function; it came out something like this:

# toy example of the function I wrote
def myfunc(arg1, arg2, arg3='some string', *args):
    # do magic
    return

And I went on doing my life normally. A couple of hours later, a flash came to my mind and I just stopped. Whait, did that just work? Indeed my function was passing all the tests I had set, but I was just puzzled.

Do you notice why? Is it really that obvious and I was not aware?

The function above just defines a non-default argument before the argument packing operation *args. Was that expected?

Definitively my brain wrote it naturally, so naturally that the conscious me didn’t even noticed, but I can tell that this was the first time I wrote such syntax in these almost 5 years I Python. There are basically two revelations here:

Firstly is that we can actually *args after a non-default argument arg3='something'. I had never seen this example before in any tutorial, how-to, whatsoever, about argument packing and unpacking with *args and **kwargs. The most complex example provided out there is always of this kind:

def myfunc(arg1, arg2, *args, kw1=1, kw2='string', kw3=None, **kwargs):
    # magic happens
    return

For someone experienced in argument packing and unpacking there is no magic in the above example, just everyday living. But the syntax I encountered today was definitively not expected.

Secondly, my brain is getting more Pythonic than me! I was actually writing something completely new for me without even realizing; simply, expecting it to work. And only noticed some hours later.

Did you knew this was possible? Let me know.