How to create an improperly closed gzip file using python?

I have an application that occasionally needs to be able to read improperly closed gzip files. The files behave like this:

>>> import gzip
>>> f = gzip.open("path/to/file.gz", 'rb')
>>> f.read()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python3.8/gzip.py", line 292, in read
    return self._buffer.read(size)
  File "/usr/lib/python3.8/gzip.py", line 498, in read
    raise EOFError("Compressed file ended before the "
EOFError: Compressed file ended before the end-of-stream marker was reached

I wrote a function to handle this by reading the file line by line and catching the EOFError, and now I want to test it.

The input to my test should be a gz file that behaves in the same way as demonstrated.
How do I make this happen in a controlled testing environment?

I really strongly prefer not making a copy of the improperly closed files that I get in production.