Today I learned that files can also be unpacked in Python.

File unpacking

After learning that strings can be unpacked in Python, I shared the short article on Twitter.

As a reply, @dabeaz suggested I tried doing it with a file:

Now, try it with a file...

header, *data = open("somedata.csv")

— David Beazley (@dabeaz) September 24, 2021

After seeing how strings can be unpacked, unpacking a file didn't look so weird, but it was still a pleasant surprise!

But it “does make sense”, after all you can iterate directly over a file, which essentially iterates over the lines of the file.

Grab a CSV file "my_data.csv", for example with this data:

Name, Surnames
John, Doe
Mary, Smith

Then, in your Python REPL, you can get this to work:

>>> header, *data = open("my_data.csv")
>>> header
'Name, Surnames\n'
>>> data
['John, Doe\n', 'Mary, Smith\n']

It is not as useful as using the csv module to read the CSV data in and process it, but it is still a nifty trick.

Come to think of it, if there is a place when this will be useful, probably won't be with CSV files...

I'll let you know if I put this little trick to good use!

That's it for now! Stay tuned and I'll see you around!

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